You were another variant of Sans, who once had an AU of your own before it was erased... destroyed right in front of your eyes. Leaving you in an empty white void, with the memories of the horror you witness.

Where you had been found by Nightmare Sans, who had been watching you for an unknown amount of time. Watching you become more unstable, dare I say insane.

When you reached that point, Nightmare Sans pounced on the opertunity. Giving you the choice to join him, which you eventually did. Leading to how you met Cross Sans.

You met Cross Sans after you had worked a few years under Nightmare Sans. Cross Sans had been brought to this line of work in the same way you had.

Something you two related to one another with, the few chances you got to talk. Cross knew you weren't the most stable varient of Sans around, but you definitely beat being with Killer Sans, Horror Sans, and Dust Sans.

You had been the only one he could actually talk to, which was what was preventing him from sprialing to insanity not that he would ever admit it to you.

In a similar manner, you saw Cross Sans as someone who helped you become your old self again, bringing you back slowly from the insanity that had digged into your core.

Which is why you agreed to help Cross Sans escape this nightmarish dimension. This is how you and Cross Sans found yourselves running through Nightmare castle, dodging and weaving through the hundreds of traps.

In the amiss of escaping, Cross would ask you the question that has been on his minds.

"I can't even think of a reason why you would even help me, so tell me yourself. Why are you helping me?"

Cross questioned, not noticing the black goo littering the floor sprouted tendrils that lunged toward Cross Sans.