(Papyrus wil be called edge and sans will be called red. Also this has plot and its pretty much Angsty fluff in a bag)
You were entering Edges house for the date that you had constantly been trying to win. Knowing you instead of leaving things be you constantly reset just so you could win the date. You hoped your friend Red wasn't catching on and as usual you made an excuse such as 'you missed something',Which wasn't far from the truth because at the end of pacifist deep down you felt emptiness like you needed to go back for something or more like someone. Edge for the longest time never came to mind until you had done everything right because the minute before Red made you reset for what felt like the millionth time you whispered his name. Red noticed that your words had a mind of their own and often heard you involuntarily mumble out words of a name but that day he finally knew the name that flew past you. Ever since then you had spent extra time on Papyrus and took the time to ask him as many questions as you could. You had at one point figured out all of his preferences and even then he still didn't accept your affections or what he had percieved as 'First time affections'. You had spent most of your time trying to get a skeleton to love you but he never loved you back.
Edge for the longest time had felt locked up in the chaos of the underground and it had eaten him up to the point where he was no longer nice to anyone but instead he turned bitter and sour with time. During your time with Edge he felt his shell chipping away because you made it so. Many of times memories of hurting his own brother made him feel guilt but only when you were around.He couldn't no matter how many times you reset figure out why you did this to him but he didn't like it in fact he hated you for doing that to him yet he never laid a finger on you. Edge had never grown up with much love so the sensation was new and very foreign though at the same time sickeningly sweet to the point it made him yack every time you left. It was like the teenage butterflies that fluttered within people who were new to romance and what it meant.
You were happy he didn't know because you knew Edge would be frustrated and he would most likely take it out on you. There were many times where that came close to happening so regardless of it not happening you were still pretty scared of his wrath.