GBA #2: Out of Mind pg. 5
Bunch of cameos of friends' characters. Doreen actually started as a Greninja I made and adopted out to my good friend DragonSushi. Sus has a full team of characters in the GBA universe called Team Math 'n' Shit, and they pop up from time to time. Check out Sus' page here - beware though, NSFW content lies within! The same applies for ElementBrigade (who lent me Samantha Stargazer the Fennekin). Tess the Spiritomb belongs to the as-of-now elusive V0yser.