Uke was a hunter/assassin who killed seme's parents years ago and seme makes it his mission to avenge them. I think seme was a vampire (not sure about this). Present time uke runs an antique shop and seme crosses paths looking for specific item that was used to kill his parents, ends up falling in love and obsessing over uke, finds out uke ended up killing his parents and basically says "oh well, as long as he doesn't leave me".
*Spoilers?* *Some info might be incorrect*
Uke was a hunter/assassin who killed seme's parents years ago and seme makes it his mission to avenge them. I think seme was a vampire (not sure about this). Present time uke runs an antique shop and seme crosses paths looking for specific item that was used to kill his parents, ends up falling in love and obsessing over uke, finds out uke ended up killing his parents and basically says "oh well, as long as he doesn't leave me".