You were Walking on Mountain Ebott when you fell into the underground and landed on a pile of Flowers you walked for a bit until you met a black Flower named Flowey who seemed innocent but then tried to kill you Lucky Sans comes in and Saves you

Sans: Heya kid... that Flower got you huh? Well, you are safe now... I'm Sans. Caretaker of the Ruins. I check here every case a human falls here again heh... follow me you'll be safe with me