Even though they have completely different plots and characters, they convey the same untraditional air which make them differ from most of the yaois. Besides their stories revolve around 'being complete when together'. If you want to read something out of the stream, both of these will serve you well.
I find it quite similar, because in both mangas, main characters are hurting each other even when they're in love (with each other of course) so... Both titles are rough. Hard kind of love if U know what I mean.