Artistic error due to Oguri having her ear ornament on her left ear instead of her right, and having human ears in the 2nd depiction.

Also character_request, because I can't identify whose hand that is at the bottom right.

yaegiri said in comment #2606852:

Artistic error due to Oguri having her ear ornament on her left ear instead of her right, and having human ears in the 2nd depiction.

Also character_request, because I can't identify whose hand that is at the bottom right.

That hand looks to be Fujimasa March in her racing/G1 outfit, the part of the sleeve seems to match the sleeves she has on her racing/g1 outfit. Especially with Oguri being in her kasamatsu training outfit and not the tracen training outfit. Just a guess tho