Okay IY fan's, I've read the manga, and seen the anime, (IY, not IY:FA) and so many fics use this as a plot device, thing is I really can't remember where this happened or if it did at all...

Just where DOES Inuyash promise to go to Hell with Kikyo?

As far as I remember they were to meet to make the wish, and Naraku tricks them, they scream about betrayal, and then She pins him to the tree. and she dies from Naraku's wounds.

Then the Kagome part of the fic happens, and well I really just cant remember it(Inuyasha) ever actually saying 'I'll follow you to hell.'

In the anime, i don't remember which episode but i think it's either the one where he made his choice and it's not Kagome or the one right before it, he tells Kaede that if Kikyo wants him to go to hell with her, he'll do it. I don't remember the exact wording but that's where it comes from.

Edit...

it's 48 Return to the Place Where We First Met

Yeah what Danyealle-sama said. I remember because that episode just recently came on Adult Swim and I refused to watch it because I knew if I did I would wanna bash Inuyasha over the head for his stupidity. It's after Inuyasha's badly injured and so Naraku goes to Kikyo and is all "Kukuku I injured Inuyasha, now I'm going to kill you" and then Kikyo is all "Pft you can't because you still have Onigumo's heart." Then she goes to Inuyasha to check on him while Kagome is in her time and she's all "I'm going to get rid of Naraku. Naraku can't kill me because his human heart still longs for me" and Inuysaha is all ">:[ HE CAN'T HAVE YOU!"

And I'm like "WTF? No duh. Stop being so jealous."

And they hug (bleh) and Kagome sees and is all D':

AND THEN SHE RUNS TO SESSHOMARU! ....Unfortunately not :<

Episode 23, Kagome's Voice And Kikyo's Kiss is the closest I can think of for the anime.

you guys rock! seriously i was having a hard time remembering just when bc thing is freaking long anime/manga wise... and there's a LOT of tween drama. i still say Kagoem should have made the beads into a chock collar!

Here is the only time it was actually mentioned in the manga.
www.mangareader.net/226-16431-9/inuyasha/chapter-175.html

-nods- so Kikyo never actually says to him " you made a promise" in the anime and manga it's Keade implying that's her(kikyo's) will, and Inuyasha stupidly agreeing to it. Kikyo just wants him dead at the beginning of the anime/manga!

okay question answered, it's ore or less that i keep seeing this in fanfiction where Kikyo's all "YOU PROMISED!" and i'm all like O_o when did he do that again?

in actuality from what we see, Kikyo never knows this full revelations, she she might want to kill him and take him to hell but she never knows of his promise to comply if thats what she wants.

things like that bother me when i'm reading so i eventually ask about them. thank you everyone!