From pixiv description:

紫「傘、差さないの？」幽「これ、日傘だから。」紫「･･･。仕方ないわね、入れてあげるわ。その代わり晴れたら幽香の傘に入れてよね。」

Yukari: Not using your umbrella?
Yuuka: Well, it's only a parasol.
Yukari: ... Can't be helped then, I'll let you share mine. On the other hand, you have to let me share yours when it clears up.