Tonikaku Kawaii TONIKAWA: Over The Moon For You
Nasa Yuzaki falls in love at first sight after an encounter with the mysterious Tsukasa. When Nasa earnestly confesses his feelings, she replies, "I'll date you, but only if we're married." Nasa and Tsukasa's cute and precious newlywed life of love is about to begin!
[Source: Crunchyroll; emended]