AlliesEditBeing the outgoing person that she is, Mavis would probably be the first to approach Hiccup, and might be very interested in his dragon. Both Hiccup and Mavis appear to live in fantasy worlds filled with amazing creatures, and since Mavis doesn't get out of the hotel very often, she would probably love flying around with Hiccup and Toothless. The two would probably get along well, also relating on a personal level since they both had trouble relating to their fathers in their movies. Beyond friendship, Mavis and Hiccup also have a ship called Mavcup, which has several fans. Mavis and Jack, despite being supernatural and immortal, are both very childlike and energetic, and they both love to explore and have fun. The two would very likely get along, probably spending nights flying around the world and visiting different places. Since they have fun-loving personalities, they are often portrayed as being very close friends, and in some cases they are even paired up together romantically in a ship called Javis. Outside of romance, however, the two are still closely associated with each other, since they are two of the few characters in the fandom who are immortal in-canon.
Both Mavis and Rapunzel were locked away from the world by one of their parents and wanted to get out and see the world. They are sometimes shipped together as the pairing Mavunzel.
Dragons are found to be somewhat common amongst the monster community (one working the Hotel using its fire to heat the spa), so Mavis would be less likely to fear Toothless from the get-go. In other circumstances, Mavis would be a little scared of Toothless at first, but then, once she sees how he and Hiccup are together, her thoughts would defiantly change. Mavis would enjoy flying on Toothless.
The relationship between Elsa and Mavis is not commonly explored within the fandom. However, most fans assume that Elsa may be cold-hearted to her, as she was to everyone else, and so Mavis would instead focus on being friends with Anna. In other interpretations, Elsa may serve as a mother figure or older sister to Mavis, and sometimes, they are even paired up in a ship called Mavelsa.
Both Mavis and Anna were locked up in their homes for many years, isolated from the world without knowing why. Despite this, they are both very optimistic and eager to see the outside world. Anna might be initially scared of Mavis because she's a vampire, but eventually, the two would learn to get along and would most likely become friends.
Once-ler and Mavis would most likely get along. While he may be freaked out by Mavis being a vampire, the Once-ler has met other supernatural beings before (like the Lorax),so he might not be very affected by it. Mavis and Once-ler have similar energetic and optimistic personalities, as well as a love for music and art, so it is likely that the two would become friends, though Mavis may feel betrayed when the Once-ler turns to greed. Beyond friendship, the two have a pairing together called Mavler, which is fairly popular.
When Dracula sees the sadness that his actions have caused Mavis, he realizes his mistake and risks his life to bring Jonathan back. After that, he apologizes to Mavis and lets her go out to see them world with Jonathan and crate her own happy life. Mavis forgives her father, and their relationship is repaired.
By Hotel Transylvania 2, Drac allowed her to marry Johnny and have a child with him. While she enjoys having him in her son's life, she can be mildly annoyed by his attempts to goad his inner vampire. She would tease him at times (like how she taught him his first words "bleh bleh bleh" wihich is known to annoy him) and even conflict with Drac's method of raising Dennis as a monster instead of a human. When she finds out that he was lying to her and potentially endangered Dennis, she decides that they were moving to California, feeling that Dennis was not safe with him. When Dracula stands up to Vlad for his cruel methods of goading Dennis' fangs, it can be assumed that this (and Dennis' sudden vampirism) convinced her to stay, mending their relationship.
Mavis' mother Martha died when Mavis was just a baby, so the relationship between the two is never truly explored in the film. However, Martha continues to have a lasting effect on Mavis' life, as she is often seen talking to her father about Martha. Martha even leaves a gift behind for Mavis on her 118th birthday, a book describing love and happiness. While they never really knew each other, most people agree that Martha would have had a loving relationship with her daughter if she had lived.
Mavis and Jonathan are smitten by one another at first sight (which they call a "zing"), although at that time, Jonathan was disguised as a monster. The two spend lots of time together and have fun with one another, despite the fact that Dracula keep trying to separate them. Eventually, Jonathan's true identity is revealed. While Mavis still wants to be with him, Jonathan is forced to leave the hotel, which causes Mavis to become depressed. However, Dracula chases Jonathan down and brings him back to Mavis, and the two are able to stay together. Jonavis is a fairly popular ship in the fandom, but since Jonathan is a mortal while Mavis isn't, some writers like to give her a different love interest when he dies off.
In Hotel Transylvania 2, Mavis and Johnny get married and have their son Dennis. While the two are still close as a couple, Mavis has a habit of letting her maternal duties get in the way, leaving Jonathan feeling somewhat neglected.
As a mother, Mavis is attentive and conscious of her son's well-being. Whereas Johnny is the "fun" parent, Mavis is the responsible one, always doting on him and looking out for him. While this comes from a good place, her attentiveness bordering on smothering not unlike what her father did to her.
She raises him as one would raise a human child and regulates what he eats to make sure that it is healthy. She would sometimes cancel appointments to take care of him - like her dates with a rather neglected Johnny - and was even planning on moving to California because she believed that he would be happier if he was around humans.
It can easily be assumed that when Dennis' fangs came in, revealing that he actually is a vampire, she has learned to relax and allow Dennis to make his own choices, choosing to stay in Transylvania.
It is unknown how well she knows Vlad or if he has ever even met Mavis, but it is clear that Mavis has known about him and values him as her grandfather. She was mildly upset that Vlad did not arrive to her wedding (presumably because Dracula intercepted her mail) and even invited him to her son's fifth birthday party before they were to leave for California. When she discovered Vlad's attempt to traumatize Dennis, she was shocked and appauled by her grandfather, verbally calling him out for what he has done. It can be assumed that Vlad's act of saving Johnny from Bela has redeemed him enoguh for her.