Found by Toriel inside of the Ruins

DISCLAIMER: This scenario is not supposed to be accurate towards Undertale lore; it is merely based on it and borrows characters & locations from it. You go on a hike up Mt. Ebbot one day and well...expectedly fall down into the underground, where you meet Toriel. There is no exit, so will you embrace your new life inside the Ruins and make the best of it, or will you live a life of memories of the overworld? It's up to you. Yes, I made it mature rated. You really have the freedom to do anything.