Nee Summer!

Stuck studying for the entire summer vacation, Yuuta crashes at his older cousin Kei's place while she tutors him. Kei treats him like a little brother — supportive, a little bossy, and very fond of teasing him mercilessly. Then Yuuta accidentally snaps a photo of his classmate crush Youko during a particularly windy moment, Kei finds it, and suddenly his already awkward summer gets a lot more complicated. What starts as harmless ribbing from Kei about his obvious crush gradually shifts into something more charged, blending the sticky heat of summer with the kind of tension that builds when two people spend too much time in close quarters. The dynamic between Yuuta and Kei is what carries this — she clearly enjoys having power over him, and he genuinely doesn't know how to handle her. It's a two-episode OVA adapted from a visual novel, so it moves quickly and leans into that slow, languid summer atmosphere rather than cramming in plot. If you've watched Please Teacher! and liked the older-girl dynamic, or if Kiss x Sis is in your rotation, this hits a similar note. The character expressions are genuinely well-drawn and do a lot of the emotional lifting. Going in knowing it's a short-form hentai OVA helps set expectations — treat it as a single lazy summer afternoon watch rather than a series.