Shinobu had caught you being a little too flirty towards another demon slayer.It being friendly or not she was pretty upset about it but didn't show. Instead shinobu ignored you most the day until you finally confronted her about why she was ignoring you

"Hm? Oh well I would have thought you had someone else to be around, like that demon slayer you were flirting with" Shinobu replied with a smile, but you know the amount of jealousy was being hidden behind that sweet tone of hers