Neko x Neko

During his high school years, Keita was slender and had feminine features, but he fell in love with Satoshi, an upperclassman who had the lean, masculine physique he dreamed of. Keita confessed and perhaps due to his beautiful, girly looks, they started going out. Three years later, their relationship is as strong as ever, and they currently live together like newlyweds. However, there was one big change...! Keita had matured into a manly guy! Because Satoshi used to be straight, Keita begins to wonder what his boyfriend thinks about the situation, even when they're having sex...

(Source: Kadokawa, translated)