Kinda disappointing, MC is... weak, it just hurts reading anything he says. He should grow pair of balls because right now he really sucks and strikes as whiny bitch that gets stepped over by anyone and anything. And the whole "I know your secret" message is stupid. Was someone camping and spying his friends house? Why? How did they do it without being noticed? For how long? So what? Both couples consented to it and I really doubt they know details unless they were hiding under table... It's just silly no matter how you think about it. I think it's best to drop/resolve that plot point asap and focus on what really matters - hot sex with married women and maybe stealing them from husbands/cheating behind their back.
Also using suffixes (-chan, -san) in western game is kinda cringy, even if it is supposed to depict japanese families.