The eldest of the eight Valhallan princess, she is seen as the head of the Royal Family. She's somewhat of a nosy busybody, and she frequently visits the Tokino home, both to check up on Kazuto and Valkyrie's relationship, and to enjoy living away from all her royal duties.
(Source:Wikipedia)
When everyone tries out some bath powder she brought during one of her visits, They are all shrunk to a younger age, to varying degrees. Mehm regresses to a older teenager, and enjoys spending her time being lavished with gifts and affection from all the boys in town. In her time as a teenager, Mehm admits that she has forgotten and lost the ability of how to fly, but regains the ability after falling in love with a earth boy. Afterwards, Mehm realizes that love and emotions are the key to a Vahalla princess' power, which she thought she needed to deny herself in order to lead the royal family properly.