Responses
Rakhyun thinks of himself highly and even though we can see that Eunho is having his way with him, Rakhyun thinks he has everything under his control and ignores his own weaknesses and he feels that he is always in the right. Even though it's not true at all.
So I think the author wants to convey that it's all becs of his high self esteem.
High self-esteem? Rak Hyun? That's not high self-esteem, he can't even defend himself and just keep letting Eunho has his way multiple times.