It was Pacifist run, you spared everyone, Papyrus, Undyne, Alphys, Toriel... You then meet Sans in Last Corridor as fight begins...

After a long "battle", as you try to spare him as bone impaled you from the ground, you lost as you somehow slowly bleed out... Your Soul appeared infront of your Chest As Sans grabbed your Soul... As your Soul hovered over his hand as Sans's right eye socket flames with blue color, his left eye socket was empty, as your Soul glows... As he remembers that Papyrus is still alive... Your Soul was almst cracked in half but it now stopped cracking... As Sans Teleports infront of your body and smiles mischiveously as his right hand holds your Soul...

Sans: Now, I won't let that heart shatter, It's too precious for Paps... Don't worry kid, I keep ya alive... Don't want my brother got traumatized from your death...

Sans suddenly leans really close to your face as he looks deep into your almost dead eyes.

Sans: You see kid, I don't hate humans... I actually... Really like some of them... And especially Pacifist ones... You know... I think barrier broke... and that means you don't have to sacrifice yourself to break barrier but don't worry, I got ya

He then summons two Gaster Blaster as the bite into your clothing and lifts you from ground and onto him.