Only vampire tummy.
Vampires who can’t hunt too well and absolutely refuse to bite into a human.
Vampires who like a specific blood type more than others, and when it comes to intake of the others they get a tummy ache.
Vampires who try to eat human food and get sick off of it because their bodies can’t handle regular everyday food.
Vampires who are embarrassed to admit that they’re vampires and got extended periods of time being “normal” around people they’ve met even if that means not be seen trying to hunt for animals and etc.
Vampires…. just… vampires tonight.
a few further suggestions…
× a type of vampire that does not need to survive on blood alone (they do need to feed occasionally to stay in their best shape, but can otherwise subsist on ‘human’ food, and prefer to do so to avoid harm to humans), who needs to plan carefully ahead for their monthly feeding. they have friends who are willing to offer an occasional portion of their fresh blood, but that’s only half of the problem. when their body begins to become hungry for blood they suffer awful hunger pangs and feelings of thirst, and they become irritable and highly-strung, but it is post-feeding they truly suffer. after the euphoria of imbibing a warm blood meal fades, they become weak and ache-y as they begin to suffer a sort of intolerance to blood with withdrawal-like symptoms: feeling sick and sluggish as their body is now unpractised in process such a rich blood meal, their head swimming with a drunkenness-like feeling. the poor, suffering vampire is in great need of their kind friends to care for and gently nurse then back to health for a few days, with plenty of bedrest
× again with a vampire that does not need to regularly drink blood to survive: a vampire that avoids blood-drinking as much as possible who, despite regular ‘human’ meals, suffers from an inescapable hunger, and a hollow feeling in their middle that filling meals just can’t sate. after spending too much time with living, breathing humans with rosy cheeks and too-loud heartbeats, they retreat to a quiet and lonely place to hug their cramping stomach and attempt to sleep away the clawing, supernatural hunger. they may not be able to feel the cold, but they are painfully aware of the absence of warm, thick blood filling their stomach — a thought that only invites another painful hunger pang
× to expand on the specific blood type thought: a vampire in a position where they can not or do not want to feed on humans, and so turn to animal blood. not only does the animal blood disagree with them — leaving the poor vampire with an upset stomach — but as they are instinctually used to human-portions of blood, after attempting to feed from a cow (or similar large animal) they find themselves uncomfortably bloated, not realising that they should have stopped drinking several minutes ago