Tsui no Taimashi ―Ender Geisterー - Vol. 5 Ch. 39 - Singin' in the rain

[MangaDex]

 

[Kaarme]

Akira should throw the needles back at the vampire Castle brother. That way he could suck spirit energy out of the dude. If that doesn't work, throw them at the werewolf brother. Then the vampire would leech from the werewolf, weakening him.