Sex Education from My Brother's Friend

With their AC busted during one of the hottest summers they've ever had, Seo-Min and her brother, Kang-Min, are desperate. Thankfully, Kang-Min's friend, Jae-Joon, has a functioning AC they can mooch off of! As the summer passes, Seo-Min and Jae-Joon start to get unexpectedly close before, completely unrelated to the weather, things start heating up...

(Source: Tapas)

Note: Part of Metatoon's Bimil Danpyeonseon (비밀(秘密) 단편선) Collection.