As said in Zoe's species Pokedex info, the fur on Storm's back grows spikey when she unleashes electricity, and/or when she uses an electric type move!

Just in case you can't tell, there is a zap/lightning shape on the front from Storm's neck fur.

Type: Dark/Electric
Ability: Static

Character belongs to me.

Purrloin/Liepard electric variant is by @MRZoet
Species Pokedex Entries: https://www.deviantart.com/mrzoet/art/Purrloin-Liepard-Variant-doodles-1097344294