@UltimateAdrian20 Had no idea about that.
@Gotim18 Haha, lol me. Totally forgot about that, read the first chapter back when it was first uploaded so I guess I totally forgot her surename. Even then my point still stands, I guess he should still know his fathers full name - unless he changed it or something. If the author decides to go with "my mom refused to tell me anything about my father" or something like that, well that would seem quite laizy.
Them being related would be quite the twist, but eh.... I dont know, a sister that is in love with her brother, then a aunt & nephew developing feelings for eachother, well that would be quite something...
This is a hard one, while I do enjoy it, I just cant help feeling that he is just some replacment for her brother wich feels really weird for me, but I'll keep reading alteast for a while.
EDIT:
@jokerxhisoka also raises a good point.