@OiGimmeMoreManga
i mean yeah she loves him and to her him marrying her is nothing wrong.
but to him its a forced marriage that also is against his own morals.
of course he is going to run away if they let him.
honestly this is all their parents fault for not even bothering explaining how marrige and all that works to him.
this all could have been avoided if he just told them he dont want to marry her as that would mean the connection between them in weak and would make a weak marriage / children
something he might have figured out if given more time then a day unlike his sister who knew it for 10 years.