Here's a fun idea that came to mind while rambling with a mutual lmao
Vampire!Spinel having a taste for your blood - enjoying it a lot, to the point that always after feeding, she ends up with an adorably tiny belly - but knowing how much she enjoys the taste of your blood, you start devising a little devilish plan; you start looking into blood magic You let Spinel feed on you again, and while she does, you use a spell that practically keeps "generating" more of your blood - Spinel was about to stop, as usual with your usual limits, but you encourage her to drink more, to her heart's fullest content, and because of your gentle, loving comfort and encouragement, as well as the sweet taste of your blood, she just keeps drinking, and drinking and drinking...
When she's done, you still feel fine as ever, and not tired and dizzy as usual - and Spinel has ended up with an Enormous blood-balloon of a belly, and not to mention her lightly drunken state
You could tease her for her sanguine thirst, gently playing with her belly, and watch her adorable flustered reactions - mayby even go as far as to use her belly as a pillow, or cushion, flustering her further as she feels all that blood of yours sloshing around in that big tummy of her's
Or, alternatively, the drunken buzz makes her a lot more flirty and playful, as she now squishes that giant tummy against you, pinning you down with you unable to escape her as she teases you for your little trick, and especially for how much you love her and want her positively full of what's practically, in a way, you
regardless, only other adorable thought that comes to mind is that after all this, the magic you used having some small side effect on the adorable pink slinky vampire, as she now always sports an adorable little potbelly, always peeking out from her clothes - not to mention her little bat form also sporting that adorable tummy, prime for playing lmao
Brain is Buzzing.mp4