All i can remember is that the ml assumed the mc was screwing around with his sister and got mad at the mc because of that and the ml had black hair the mc had blondish hair
https://www.mangago.me/read-manga/kiss_me_if_you_can/
maybe https://www.mangago.me/read-manga/no_return_after_use/ ?
All i can remember is that the ml assumed the mc was screwing around with his sister and got mad at the mc because of that and the ml had black hair the mc had blondish hair