A couple E. Gadd headcanons:
1. He isn't the only paranormal researcher by any means; in fact, in the Mushroom 'verse, it's respected as a field of research. However, E. Gadd isn't very respected by those in his field, given his oddball hypothesis that ghosts are real, living entities and just his quirkiness in general.
- Gooigi, Robo Mario and Stuffwell all live with him. They're basically family.
- Even though E. Gadd is very much capable of uploading plumbing, carpentry, etc. programming into Robo Mario, he hasn't. Any time there's a plumbing issue or one of his inventions causes damage, he rings up Luigi.
- It's essentially his way of making sure Luigi visits him, since he spent a long while by his lonesome without any human interaction until he happened upon the plumber in Luigi's Mansion.
- Luigi has been trying to invite him over to the house more often because of this.
- Despite literally creating multiple vacuums, if it wasn't for Stuffwell and Robo Mario's help, E. Gadd's laboratory would be a mess.
- E. Gadd is a terrible driver. Luigi rode with him once and swore afterwards he'd never do it again.