Acticate button script - need help scripting

[Galejro]

I'm working on a first mod with CK and so far it's going well. But I'm no master scripter so I eventually had to run into this snag, that's why I'm asking for help. I'm working on a vampirism mod and inevitably I have to make it so that the player can do something like sandman perk effect.

 

I need someone to help out in making of the scripting for a perk and how to make such a perk, or scripting for a button that can be visible in sneak mode on a sleeping NPC. The feeding effects I already got scripted for bloodpacks, but I need the module that allows to activate that with a button like defult "R" for a sandman kill, preferably with a fatal effect as well.

 

Of course that's the ideal, if anyone has other ideas I'm open to suggestions.