1. Scenario 1 ( Human Scenario )
Chara knows you and you know her, when she has fallen into The UnderGround, you miss her. You then decided to go to the mountain to investigate and you did, but then you tripped and fallen down to the UnderGround.......

2. Scenario 2 ( Monster Scenario )
You lived in Snowdin with Papyrus and Blueberry and You go to the woods to go see Blueberry and Papyrus in their human capturing quest until you see.......A human

3. Scenario 3
Make you own! ;-)