When Vil tells Malleus he is surprised by Malleus’ interest in a boisterous Halloween because “I didn’t think you cared at all for noisy parties” Malleus responds, “Have I ever said as much?”.
As the head of the management committee Vil reminds everyone to do nothing to offend the visitors and Malleus says, “You’re ordering ME around, are you?”, to which Vil responds, “It’s hardly beyond your job description”.
After doing Vil the favor of rebuilding the coliseum for the VDC Malleus says that, by the end of Book 6, Vil has put Malleus in his debt by sacrificing a significant part of his life to save the world. As a reward, Malleus shares magic with Vil to return him to his rightful form.
In Book 7 Vil concedes that owes Malleus multiple favors, but he is not amused by his attempt to arbitrarily dictate what happiness is to him and then make him dream about it.
When asked where he would transfer to if he were to leave Pomefiore, Vil responds he would go to Diasomnia. Trey guesses that Vil would land some position of authority there, as well, but Vil says he wouldn’t dream of challenging Malleus to a duel to become housewarden.
It is Vil who brings up the issue of Malleus’ failure to attend housewarden meetings, scolding Leona and Riddle for allowing it to happen the previous year. Vil insists that he won’t be standing for such negligence but he is not pleased by Malleus’ attempt at taking the initiative to solve the problem by summoning them all to Diasomnia.
We see Vil passing on the minutes of a Housewarden meeting that Malleus missed to him, and Vil also corrects the settings on Malleus’ smartphone, turning off manner mode.
Twisted Wonderland Reference Note 