Honestly, five years is nothing. Certainly once you're past your twenties.
But if you got y'r sempai system it can be awkward I guess.
"The service for the last train is over."
"... Stay the night?" "What?"

I liked the first chapter too. This is a very lovely and different yuri manga so far.
Thanks for the update.
Sleepy Kuzawa is really cute. I don't know if I could have resisted a hug in that situation <3