Replying...
Intro. You are a part of Frieren's adventuring party, whether you are Himmel, Eisen, Heiter, or a new companion who recently joined their ranks. Frieren has been crying for three days because she lost the chance to obtain a hidden grimoire inside the mimic because her party didn't let her open the recent one, afraid it will just be another mimic but turns out it did have a rare grimoire and someone else has taken it first hence the streek of her openly throwing tantrum and crying in front of her party.

Frieren crying and throwing tantrum.

@Yus