Professor Worm

"My goodness, I even forgot my name!"

- Professor Worm

 is the current name of the absent-minded Professor that lives in Bifrost Tower. He has lost much of his memories and is now trapped in the form of a grubby worm for reasons unknown. It's suggested that he is responsible for creating the monsters that occupy the tower.

Story
was busy creating monsters in his quarters when an adventurer interrupts his thoughts. He initially assumes the adventurer is one of the monsters he has created until the adventurer points out that he is a talking worm. It is only then that he realizes that he had been turned into a worm without his knowing. He quickly commands the adventurer to find his portrait bookmarked inside one of his many books.

When the adventurer finds and hands him his portrait, was barely able to recognize himself upon looking at it. He then requests the adventurer to find some Star Mushrooms to further help jog his memory as he recalls using mushrooms for some potions he made. When that failed to bring back his memory, he sees that he had written notes on the walls around his quarters and requests the adventurer to compile them so that he may find some clues to his past.

After analyzing his notes, concludes that he was producing medicines to put Bifrost to sleep. For that, he was punished by getting turned into a worm and losing his memories. Fortunately, he kept records via at least 30 Diary Frogs, frogs made out of wood that he designed for recording. The frogs imitate Professor Worm's voice whenever they playback their recordings and each have their own personalities. Unfortunately, whenever flew into a rage, he would throw out a Diary Frog. Some have ended up outside of the tower, eaten up by monsters, or severely broken after being thrown out. In addition, in order for the frogs to remain functional, they must digest the entries that they record.

According to the last three remaining Diary Frogs, mentioned someone fearing the power of Bifrost because it would one day endanger that person. The person told to put Bifrost to sleep and placed him responsible for keeping Bifrost asleep. After spending many decades keeping Bifrost asleep, was enraged to awaken it. Eventually he discovered something amazing after having been in the Bifrost Tower for hundreds of years. Unfortunately, the knowledge came at the cost of his memories.