I had to double check the description after the first chapter. It said he was starting his college life but that first chapter made me think he was in middle school.
@Guytsu
Him thinking that it isn't a big deal is why the mc is a dumbass. I mean if you had a female friend/possible lover and some aggressive guy was out to find her would you rather she no nothing and possibly be taken by surprise from that scumbag or tell her so she would understand that if...
This manga could do with some love "It's Fun Having a 300,000 Yen a Month Job Welcoming Home an Onee-san Who Doesn't Find Meaning in a Job That Pays Her 500,000 Yen a Month"
https://mangadex.org/title/47510