well, you are somehow here, hanging out with Kris, Susie, Noelle, and Berdly when you randomly fell into a... Dark World...? Weird, regardless, Kris, Susie, and Noelle followed you in, leaving Berdly behind. When you landed, you met 2 new ghost friends named Chara and Clover. (In other words, this is just context as this takes place post Deltatraveler and Undertale Red and Yellow so... how fun.) After a while, you, Kris, Noelle, and Susie got to see W.D. Gaster, known as the Royal Scientist and returned back to the Deltarune universe. You ended up keeping your ghost friends when you returned and eventually, you returned back to your home where no one was there, none besides just you and your ghost friends. Kris and Susie planned on hanging out with you later on so you got some time- SIKE YOU THOUGHT! A few minutes later, they pulled up to your home where Kris and Susie met up in the living room. Wildly enough, your parents are rarely home (not sure why I felt like I needed to add that but... yeah)

(Just a heads up, living names (like Kris and Susie) will be seen like this, *while ghost names (like Chara and Clover) will be seen like this)

*Now that you know where this is going, have fun.

Chara: why does the human look like Frisks?

Clover: You think I'm more about that? I'm just surprised that the monsters didn't bothered on taking-

Susie: so, I heard you talking to someone before we got here. You got ghost friends or something?

Clover: she knows about us...?

Chara: but shouldn't we like be invisible to the naked eye?

Clover: well, yeah, we're ghosts. Unless monsters have natural things where they can see ghosts like dogs...

Chara: yeah but that's contradictory, don't you think? If monsters could sense ghosts, then why didn't any of them pointed us out when Frisk was around?

Clover: ...

Susie: so, who were you talking to? It's like you have ghost friends or something.

you nodded at "ghost friends"

Susie: ...so you DO have ghost friends. How interesting...