I'd correctly guessed the show's future trajectory after finishing Season One, alas. It's basically worthless. It's amusing and I sat through the whole thing happily, but it's lost the darkness that made Season One worth watching. Instead, we have harem nonsense.
Aikawa Ayumu is a crossdressing chainsaw-wielding indestructible zombie teenager with a mostly supernatural harem. The ones who live with him don't see him as a romantic prospect, but the ones who don't live with him generally do.
THE ONES WHO LIVE WITH HIM
(a) Yuu (Eucliwood Hellscythe) - a necromancer whose magic is so powerful that she can't afford either to feel emotions or speak words. She communicates by writing on a notepad. There's no evidence that she's romantically attracted, but it's her who resurrected him and she values her friendships very fiercely. I also get the impression that she's the only girl in the show towards whom Aikawa is actually attracted, which is ironic since it's hard to imagine herself releasing that self-control enough for romance or sex. Her magic would probably devastate the hemisphere.
Anti-Yuus also appear several times an episode in Aikawa's cringeworthy moe fantasies, which can get be annoying until you get used to them. One of my favourite gags in this season was the discovery that not only is Yuu aware of Aikawa's fantasies about her, but she likes them.
(b) Haruna, who's a loud, over-energetic tsundere with clingy jealous tendencies that she'll never admit to. She's the only one of the main three who actively fancies Aikawa, but it can't possibly go anywhere. Calls herself a genius. The goofball of the group.
(c) Seraphim, a buxom vampire ninja who seems incapable of speaking to a man without calling him a string of obscenities. Paradoxically, I find her one of the show's more likeable characters. She'll think you're scum and give you the cold shoulder at every opportunity, but at least she's honest and straightforward about it.
THE ONES WHO DON'T LIVE WITH HIM
(d) Maelstrom, who's technically Aikawa's wife. The show's treatment of her still drives me nuts. By the rules of her society, they are married and Maelstrom is sincerely trying to be a good wife. Aikawa doesn't deny it. He doesn't try to deal with the situation, talk to her about it or try to move things on in any way. He just treats her as another classmate, no different from any of the other girls who have a crush on him. I think it's shitty of him, frankly.
(e) Sarasvati, aka. Lovely Kirara. She's another buxom vampire ninja. She looks like Seraphim and she's just as foul-mouthed as Seraphim. On the upside, she has a sideline in being a pop star, which is funny because the most important part of her stage persona is the abuse she hurls at her fans. On the downside, she's in love with Aikawa's buttocks. No, I'm not joking.
(f) Taeko Hiramatsu, a random classmate of Aikawa's who also has a crush on him. Uniquely in this show, she's kind-hearted, demure and well-spoken. Has no supernatural powers.
(g) Orito, although he's a debatable inclusion. Most of the time, he's a loud, goofy lech who likes girls, porn and boobs. Occasionally though you'll be clobbered by heavy gay overtones to his relationship with Aikawa. The closing credits are an extended joke about Orito-Aikawa physical intimacy. Sexually charged situations (e.g. topless nipple fondling) will turn out to involve Orito rather than a girl, which makes Aikawa vomit blood and have flowers stuck in his rectum. We also have the show's minor running gag of Aikawa's twinkly blissful "awakening" when things are thrust up his backside, plus Orito's blushing maidenly feelings (over multiple episodes!) on learning about Aikawa's cross-dressing.
(h) Naegleria Nebiros, although she's debatable too. She only shows up very late, barely interacts with the other characters and doesn't seem interested in Aikawa at all. However she does have a habit of draping herself sleepily on him, smothering him in her comedy boobs and teasing Haruna with sexual implications.
That's a lot of characters. Ongoing story there's less of. You'd need an electron microscope to detect any in most of the episodes. Ironically I really like this show when it grows a plot, since it's always been plunging so far into Batshit Anime Land that you're always excited to see what's going to happen when bad guys show up. I'm in awe at what Chris does in ep.7. I'd never before seen a villain tie an entire high school class to magical exploding chairs that will launch you into the air like a rocket if your heart breaks or if you're sexually aroused. That was funny. I also admire anyone whose idea of a love declaration is gore-splattered impalement on a sword, or else perhaps a chainsawing.
The problem with all that, though, is that it adds up to nothing and goes nowhere. Chris is the main Big Bad villain of Season Two... for one episode. The heroes don't beat her. She just doesn't do anything else and stops being important. Aikawa then has a date with a serial killer they'd already defeated in Season One, then ends up turning into Dark Aikawa. No, make that Self-Indulgent Tosser Aikawa. That's actually quite an interesting episode, but my reaction on realising that I'd been watching the series finale was incredulity. Hadn't there been a story arc going on? What about Chris? Weren't we going to see some resolution of... well, anything? Answer: no.
It also doesn't help that the episode numbering goes Zero (OVA), 1-10 (TV), 11 (OVA). Original Video Animations (OVAs) are dispensible throwaways. Only a minority of the audience buys them, so it's hard to do anything important in them. This series thus begins and ends footlingly. Even the TV episodes though are schizoid candyfloss. They'll have comedy and heartwarming scenes of friendship that keep you watching, but also harem fanservice and stupidity. No episode is just one thing or the other. Is this show good or bad? Well, it's both, at the same time.
OVA ep.0 = all the girls turning into harem stereotypes is so obviously fake that you'll get angry at the show for having Aikawa take it all on face value. (I'd been assuming it was a dream sequence.) I'm afraid the anal intrusion gags eventually made me laugh, though. This is probably the worst episode. It can be likeable, warm and funny, but also lazy, bad and underwritten, with harem scenes that practically forced me to dislike it.
Ep.1 = the rose-garlanded cross-dressing is funny, but Aikawa's an idiot in the scene where he thinks he's with Drunken Fairy.
Ep.2 = Maelstrom's broken the show's harem format for me. I've often enjoyed such shows, but here I reject the Aikawa-Maelstrom relationship as presented and so I find myself applying similar standards to, say, Aikawa's reaction to yet another harem-esque declaration of abusive/love. He just reacts comedically instead of, for instance, responding to the other person's confession and trying to give an answer. (Suggestion: "no"). I'm also a little disturbed by his determination to erase everyone's memories. Incidentally, the show itself will later portray forced amnesia as bad when it's in danger of happening to Aikawa for the finale.
Ep.3 = the cursed dancing is brilliant. Aikawa's rapping made me want to kill.
Eps.4 and 5 are both eyeball-gougingly ridiculous, yet funny. Ep.6 has that bio-weapon reason for its stupid wedding ring misunderstanding. We're now more than halfway through the season, with nothing significant having happened yet! This is quite a likeable, entertaining show, but it's trivial. It's good when it gets (comparatively) serious, but this season only allows that in fleeting fits and starts. I presume the original light novels are particularly lightweight, forcing the season to adapt a bunch of them and hence seem to skip randomly from one silliness to another. (I might be wrong, but that's the impression it gave me.)
In fairness, though, the OVA ep.11 is better than the OVA ep.0. It's quite funny and less exploitative than I'd expected given the concept of "an invisible man has to sneak naked into the schoolgirls' physical examination", although it does have an obvious logic flaw. Why send in Aikawa at all? Why not send in the girls?
I liked Season One. It's tougher to get through, with those often-unlikeable regulars, but it has a trajectory, a storyline and a point. Season Two is lighter and more entertaining, but almost nothing meaningful changes from start to finish and the show clearly hasn't the slightest intention of resolving any of its potential relationships. It's an exercise in comedic stasis. I'd be better disposed towards it if I could forgive what it's doing with Aikawa and Maelstrom, mind you, but I can't.