>>283257917
She started working overtime so she could spend Christmas with him.
His new boss asked him out first and senpai got pissed her plan didn't work out and told him to go with her.
The boss asked her to join them, it wasn't a date or anything, even his sister showed up later on, but she didn't want to.
She took on extra work because one of her subordinates had a date with her boyfriend, new trainee helped her and asked her out.
She went with him because she felt obliged.
It just happened to be the same place.
No NTR, no misunderstanding, only senpai being stubborn. That being said them starting to trial date and it never amounting to anything is lame.