At times, she often woke her up
If she found her sleeping during the day
There was a reason for this
She almost lost her
In that sea of red
She mostly woke her up
Just to make sure she was
Still with her
She is patient with her
After all, she caused her this much pain
Staying up most nights to
Help her sleep
At the moment, she'd assuage her worries again
By holding her close, as she slept
So, Little Sister
"I'm still here...
Could feel her heart beating
Reassurance that her big sister will stay
"...and I'm not leaving, anytime soon.."
—Written 9/25/2023
Authoress Notes:
While Satsuki is on sleeping medication for her insomnia (as alluded to in 「Remember your medicine」 and Repressed Nightmares), she does tend to forgo it to comfort Ryuuko during her nightmares, so there are times where she'd be sleeping during the daytime hours, as nighttime insomnia can make a person dead tired during the waking hours. Why would this scare Ryuuko? Well, headcanon has it that Satsuki, especially during the day, would be light sleeper usually, so a dead tired Satsuki can look, well, dead, especially considering that day.
Being held close enough to feel Satsuki's heart beating can be comforting.