[Some spoilers]
I read vol. 2 in spanish.
Hmm... not really, well, it depends on your thoughts about AV actors and their work.
The event occurs due to an acting role that Izumi got, because he needs money so he can become dependable before confessing his love to Asakura.
ヾ(￣▽￣)
DEAR JESUS PLEASE ELABORATE. NHOOOOOO I REALLY LIKE THIS MANGA TOO!!!! （/TДT)/
He didn´t cheat with sex, it was just a kiss within his acting.. nothing more..
Through a very rough translation it was a lot more than just kissing.
I read the raws, he cheats on him later. Stupid. Don't continue reading!