I think that the Crown Prince is a work of sh*t (︶︿︶)=凸 Pardon me for the bad word but I just can't think of his reason as a justification for having an affair right in front of Melissa..
Also I think Melissa misunderstood her father's actions and I think that he just doesn't know how to approach her because- well, the both of them don't bother interacting with each other ( ̄∇ ̄")
Can't wait for more chapters ヾ(☆▽☆) Thanks for the UPDATE!