If you're looking for manga similar to Chibi Vampire: Airmail, you might like these titles.
A vampire, a werewolf, and a Frankenstein monster live in a castle apart from humans.
Vampires now coexist with humans by forming contracts with human beings. Vampires who form these contracts become their pets, serving their every need. They are given pet collars, distinguishing them from wild vampires, which are still very dangerous. Daichi really wants a pet vampire, but his older sister won't hear anything of it. One night, a wild vampire princess named Iko breaks into his house! Iko discovered that Daichi's older sister has the extremely rare blood of Chernobog, which she believes would make her powerful enough to destroy the anti-vampire organization called Abraham once and for all. However, the blood doesn't work exactly as Iko expects, and this vampire soon finds herself forced to become the pet of Daichi and his older sister...
The vampire Drushle, who carries the fate of his clan on his shoulders, is extraordinarily weak in blood. Suddenly, a schoolgirl appears before him..?!
Tsukina Ishikawa is a vampire. The cool and mysterious beauty is the most popular girl in class! But it turns out she's not very good at sucking blood?
Kentaro, the vampire finds himself almost being eaten by Otsuka (seiki-sucker). But of course Kentaro doesn't die from it because he has eternal life. He decided they should live with each other and keep each other alive, one by sucking blood and the other one by sucking seiki. Slowly the two of them begin to feel more for each other then just food.
Kahoko is like a lovely princess who looks good carrying a parasol. However, she’s actually a half vampire who can’t handle horror movies! She longs for a love like that of normal humans, but whenever she gets into a good mood with her beloved Komaba-kun, fangs start to show... She’s in agony between her instinct and her reasoning...
Hisoka is a girl who tries out black magic to punish her former and worst boyfriend. But as a result of this she summons up a Vampire named Rain.....!! He tells Hisoka that he will grant one wish for her, but for a compensation she must offer her blood to him. At first she was afraid of him but she's beginning to be attracted to the vampire who's kind and a bit strange......?!