Shimarin and bonrin are so fun for me in different ways, and the only way I know how to explain it is that: Ryuuji wants to help tame Rin’s demonic side, it’s a feat that is possible, Rin can do it, and as far as I’m aware in the current progress of the manga, has done it. He takes all of Rin’s strength and power and the risks that come with him being a demon in stride and still sees the boy inside of him to be loved.
But Shima who has hidden his apathy from the world, has expectations and penance forced on him for others decisions (his brother saving him) likes to push Rin. Not in the “don’t you want to go psycho and burn the world down?” Kind of way because he then would get burned too, but in a dangerous “don’t you wanna let go just a little bit? Don’t you want to be self indulgent? Don’t you want to stop caring what they all think?”
And it’s dangerous for Rin who always needs to tread this line of demon and human, keeping each side of himself in balance.
TLDR in a way, I can see Bonrin with the happy ending. A good relationship, marriage even, it would take so, so much work from both sides. Compromise and communication and mainly commitment of course. But shimarin I don’t think could ever get there, they’d burn bright and hot and fast and eventually all there would be is their ashes with no soil to nurture it with.
(Of course that won’t stop me from writing fluffy aus where they do get a happy ending XD because I am a sucker for love being able to prevail).
