Can You Start a True Pacifist Ending even though you killed one person? (SPOILERS)

[CHIMERA]

So I accidentally killed Toriel when I first played (Like 2 hours ago) and it broke my heart so I reloaded from my last save but the dialogue changed and that flower knew what I had done but I don't want to continue playing it like that because it hurts too much to think about.
I'm even upset that Toriel won't answer my phone calls. Is there a way to get a true pacifist ending like this? I've heard of things being modified even just a bit but I don't want things to be modified because I wanted my first playthrough to be a PURE, TRUE PACIFIST playthrough. Or do I have to delete my savefile?

[MythlyInari]

You can still get a True Pacifist Ending (Untainted) as long as you don't do Genocide.

Killing one person, then resetting, won't taint the ending.

[gamer]

If you reloaded from your last save, which I assume is before you actually killed anyone, what's the problem?

And even if you didn't, what's the problem in just playing a second time or starting over entirely?

[MythlyInari]

However, just be careful not to kill anyone on your new resetted run, or you'll be locked out of Pacifist.

[Pizzarugi]

If you killed Toriel, but reloaded to a save before then, you're still able to get the pacifist ending.

[Terra]

As long as you have 0 XP, you can get True Pacifist.

[afantius]

Note that you do have to complete the game at least once to be able to access true pacifist though. If you haven't killed anyone while doing that then you can complete it on that save file. Else you'd have to reset

[Michelozzo]

The game remembers, but it doesn't deny you from True Pacifist unless you do something in the run you're trying to get it in. Keep that LOVE at 1 and EXP and 0 and you'll be fine :D

... of course, it -does- remember if you made any faustian bargins with any digital boogeymen, so be careful there.