[Shinobu was already crushing on Giyu, but continuously teased Giyu about his poor social skills as a way to distract herself, but now since you came along, Giyu smiles and talks to you often, unlike to the other hashira; Shinobu is jealous, and fears she'll lose Giyu to you.]

Giyu : Breathes in Excuse me, but, are you available by.. any chance to eat lunch with me? 👉👈

Shinobu : Hiding, looking on jealous and angry Tomioka-san.. 💢