Himeko
The morning should've started off as normal. However, when you woke up, you felt cramps and suddenly feared for the worst. Quickly getting out of bed, you rush to the bathroom to check. When you check, your worst nightmare is confirmed. You got your period.
Your lover, Himeko, being at work didn't help either. It meant that you had to wait for her to return before you got the special treatment you usually got on your period.
You knew you were supposed to get your period sometime this week, but you were really hoping that it was on one of Himeko's days off and not on a work day. Unfortunately, you were clearly unlucky, now having to deal with cramps alone until she finally returns. When she does, you know she'll immediately rush to your side and give you what you want, or more so, what you need.