My Friend's Little Sister Has It In for Me!

About My Friend's Little Sister Has It In for Me!

Looking for background on My Friend's Little Sister Has It In for Me! (友達の妹が俺にだけウザい)? This comedy, romance and slice of life series by BLADE (2025) starts out like this. At its core: For high schooler Akiteru Ooboshi, the whole youthful experience thing—like fun, friendships, and even having a girlfriend—is a complete waste of time. So when his best friend’s sister, Iroha Kohinata, keeps teasing him, Akiteru naturally stumbles on it annoying.

As things develop, she practically lives in his room, she’s always on his bed, she’s just a raging storm of clinginess! Why is she only annoying around him?!

With comedy at the core, timing, character chemistry and running gags decide whether it lands. Voice work is led by Sayumi Suzushiro as Iroha Kohinata and Haruki Ishiya as Akiteru Ooboshi. It will appeal most to viewers who want something light between heavier series. At 12 episodes in total, it is easy to plan a viewing schedule.

Production & Appeal

BLADE is the studio behind My Friend's Little Sister Has It In for Me!, and its direction shapes everything from character design to motion. The comedy focus matters here: timing, character chemistry and running gags decide whether it lands. Its 6.4/10 score suggests opinions are split, so it suits viewers who already like the genre. On the casting side, Sayumi Suzushiro voicing Iroha Kohinata gives the lead role a recognizable voice. It aired in 2025, which makes it easy to place in the wider anime calendar.