NETOGE NO YOME GA NINKI IDOL DATTA: COOL KEI NO KANOJO WA GENJITSU DEMO YOME NO TSUMORI DE IRU

Kazuto Ayanokouji is an ordinary high school boy. He spends his days playing online games as a hobby. One day, he discovers the true identity of a friend who is so close to him that they are married in-game. It turns out to be a cool idol from the same class, Rinka Mizuki. As Rinka tries to act as his wife in real life, Kazuto is forced to lead a dizzying life. — Description from AniList community (anilist.co).