It's based on a four-panel gag manga and it's light and charming. I laughed. It's doing pretty well with the three-minute format and I'd recommend it.
It's about the home life of five siblings whose parents live abroad. (The show almost never takes us outside their apartment, although I think ep.4 lets us follow them shopping. We never see them at school, though.) Our five heroes are:
MUTSUKI (18, f) - the oldest and the most responsible. She's Miss Perfect in front of her sisters, but a bit of a slob when only Haruki's around.
HARUKI (16, m) - the long-suffering main character and the only boy. He's a bit of an otaku and he likes playing computer games, of which he has an insane number. He also used to be a bit chunibyou (i.e. wallowing in a delusional fantasy world), which is one of the show's better jokes.
YAYOI (15, f) - athletic tsundere, often violent.
UZUKI (7, f) - pink-haired, girly and outgoing. Always goes around with her twin sister...
SATSUKI (7, f) - purple-haired, quieter and the only sister who shares Haruki's otaku tastes. She'll read his manga and even watch its anime adaptations on TV, for instance, whereas Uzuki isn't interested because it's for boys.
It's a slice-of-life comedy. The siblings bounce off each other and do silly sibling things. There's an episode about the twins trying to eat hot curry, for instance, because they object to being handled with kid gloves. The twins were my favourite characters, actually. The show seems to write itself when they're around, since they're just children doing typical children's things. They're fun.
There are also no incest jokes with them around, thank goodness. (Well, nearly. One episode actually goes there, for double the horror, but of course it's all just innocent silliness that means nothing except a scare for Haruki.) With the older three, though, there's more. It's just frivolous subtext and nothing's ever going to happen between them, but incest tease is the show's fallback joke and there's quite a lot of it. Mutsuki likes lying in Haruki's bed and doesn't think it's weird to wake him up in the middle of the night to practise kissing. (She's taken a role in a school play.) She's the curvy sister. She's probably just a bit dozy and lacking in self-awareness, but she does seem a bit too ready to believe the worst when Haruki and Yayoi are open to misunderstanding.
Meanwhile Yayoi is your standard tsundere, beating Haruki up for perceived bad behaviour and then possibly blushing. She's the closest in age to Haruki and they talk as equals, in a way that's not true with the other sisters. As for Haruki, he's basically the straight man, although like Mutsuki he's capable of taking misleading situations a bit more seriously than you might think wise or normal. Real siblings would take all this nonsense in their stride, but then again we are talking about the show's default gag.
That's a lot of comedy set-up for three-minute episodes. It works. You'll almost forget that it's a short-format show, because the characters are drawn so quickly and clearly that it doesn't feel different from any other show. You immediately feel you know and like everyone. They make you laugh. The comedy doesn't feel cut-down or abbreviated. Besides, the incest tease is being undercut all over the place and the show's essentially just a light-hearted slice of life. It's fun and happy. The twins are particularly nice. I enjoyed it a lot.