When a YouTube video ridiculing his attempt to feed off a millennial makes him a laughing stock, an ageing vampire rallies his fellow ageing monsters to remember their roots and terrify the community until mankind dare not venture out after dark.

"When he becomes a laughing stock on youtube; after being pranked by the millennials he was trying to feed on, an aging vampire rallies his brethren,? inserts?his dentures and goes to war with his soy eating, beta harassers."

You should use the term 'Millenial' instead of virgin because it will make the vampire more likable.

Maybe instead of 'fearing' the old vampire, the Millenials take mocking selfies with him and posting their hurtful photos online.

Possible title: Grampire

(Gran Torino meets love at first bite)