Trigger warning: forced little, vampire, kidnapping, blood, drinking blood
This isn't my prompt but I can't find their original owner)

A and B are best friends but one day A goes missing. B searches and searches with no luck until one day he finds A but everything goes back. Next thing he knows he wakes in an adult size nursery. Next thing he knows there's be talking to him as if he was a child. Then the craving for blood hit him. This was going to be hell.

Later in roleplay it is explained that new vampires more so ones that were biten tend to be rude and baby like when first turned. A couldn't have his baby act like that.