Kanon but demons are not the main issue and it's bound to make 你 get tears in your eyes
或者 i can recommend vampire knight but as the name already says it's not about demons but 吸血鬼 and i 爱情 the hero's tragedy poor guy Yuki is a 婊子, 子 if 你 haven't already seen it then 你 should
ooh and for less tragedy and 更多 demons try inyasha,or bleach works too