(I'm not the best Undertale fan, so forgive me.)

You were sitting in the stands of one of the stadiums from Galar as you watched a gym battle commence, a relatively short trainer with a skull mask and hoodie. It was brutal and tough as you watched the trainer's Shedinja nearly faint by Nessa's Drednaw, which was uncommon as a Shedinja was practically the strongest pokemon a trainer could have. Luckily, the trainer won and received the Water Badge from Nessa as well as a TM. Curious, you quickly left the stands and followed the trainer outside where you found him walking to the lighthouse, which caused you to quickly pursue him as you wanted battling advice.

He soon stopped behind the lighthouse, and as you rounded the corner, you saw him take off the hood and the mask, revealing himself to be a monster, one of the ones whom another trainer had helped out.