I think I saw how to make one is this thing I was told to read before asking questions but I can't remember what that was. --- Now Playing: Patapon (PSP), Uncharted: Drake's Fortune (PS3), PixelJunk Monsters (PSN), Super Mario Galaxy (Wii) Now Hyping: Echochrome (PSN), Patapon (PSP)
You need to fuse a Jack Frost using any two personas that will result in a Magician-arcana persona. The average levels of the personas must be between 5 and 8.
Then you need to get Jack Frost enrolled in medical school. It's difficult, given that you have a very small window of time to actually complete the game, and medical school is a long and complicated process (usually taking several years), but don't give up. Talk to Mitsuru; perhaps she can get him a room at the dorm.