It is gonna be Jiip.

I can just picture him finding Dente's cave & forcing him to becoming what Shoma is and become a half-Granute to match him in power.

If he becomes Bitter Gavv, I'd imagine him going after Sachika, Hajime, along with everybody Shoma's made contact with.

He'll force Shoma to transform into Gavv in front of everybody.

Yeah, my chips are on him too. But if the writers decide to make Jiip the red herring, Suga, maybe? He's crazy enough to do it with the help of Nyelv. Still, I think Jiip will be the one.

Looking at the weapon, BitterGavv is giving me DonMurasame vibes.

I like the pun on how elongated "yami", meaning darkness, becomes "yummy".

Zakuzaku or Hirihiri?

Damn, this is hard. :lolol

That too.

Something feels off about the Jiip as Bitter Gavv theory... I can't quite put my finger on why, but I'm getting a hunch that it might actually not be an external enemy at all, rather an embodiment of Shouma's dark side somehow. Possibly a clone or split-off copy of him, or maybe Shouma himself, since a lot of Reiwa riders have dark/berserk forms. Gotchard is the only one so far who IIRC didn't have any (I forget if Iron Gotchard was one), although Geats's was Boost MkIII which only appeared once. And given that Shouma is literally half monster already I'll be surprised if he never gets one

I still think its Jiip.

He'll find Dente and force him to remodel him a half-Granute to match with Shoma's powers.

Bitter Gavv won't work for Shoma. Dark Gavv would be fitting name for him if he ends up eating a Dark Sweet that turns him evil and unleashing his Granute self.

Hm, I didn't consider the split personality route until now. The whole "Jiip is vengeful" angle had me convinced, but mechanically speaking, Shouma's Gavv is unique to him being human and Granute, so there's that. Unless, Nyelv and Suga somehow figures out a workaround and augments Jiip.

Unless Nyelv & Suga would find Dente and have him forced to make Jiip the same way Shoma is.

Yeah, that's a possibility that I am still open to as well. FairyKing's speculation is convincing too though considering Shouma's trait of creating Gochizous by eating snacks still seems unique to him within the narrative.