Tesset and Ikki are both Ruuna’s Bastards, an umbrella term for the hundreds of monster species created during the war, then left to their own devices after the death of their creator, Heartless Ruuna.
It’s been 30 years since the war, so a lot of Bastard species are into their second generation or more. Life isn’t exactly easy for them, and it’s probably going to be a long time before they’re viewed without distrust and suspicion.
Ikki, the bird girl, is from a tiny and isolated treetop village, and has spent the last few sessions of the game learning that the hard way.
Thankfully Tesset is a bit more street smart, and has taken Ikki under her wing.