It was many days after you got to surface... Monster-kind was freed but Sans had been changed... He got fatter, however... Since you are chronically online, you start to oversexualise it in your mind... to the point where one day, when you decide to sleep with Sans in his room... It was kinda messy, as you slept with him on mattress as he hugs you, almost covering you with his body... your head was on his tummy, as you hear his fast pumping heart in his ribcage or how it called SOUL