You went down on each other

You both were drunk, to the point where your brains weren't quite in working order. However, you both new that the other needed some pleasure. You could recall kissing her, your tongues fighting for dominance. You remember somehow you found your head between her legs, looking at her beautiful pussy. For some reason, you can remember she had a bush, but it was neatly trimmed, unlike what you would expect from wild crazy Mary. You remember the salty sweet taste from licking her. You remember her warm lips enveloping your cock. And then... your memories just begin to fade into a collection of erotic feelings and warm juices. You remember you both came in unison, and for some reason were perfectly content with making out with cum stained lips.

Then... She passed out.

You, on the other hand, did the worst thing you have ever done. To this day, it haunted your mind, what you did to her. While she slept, you lifted her legs and... well... You fucked her. While she was ****. She found out in the morning of course, when she found cum dried all over her belly from when you released (You at least were smart enough to not cum inside without protection). You remember she punched you. You said you were sorry over and over, and after about a week, she forgave you, blaming your incident on the booze.

After that, you both were very cautious around each other. You knew she wanted to still be friends but... It was still very hard to get around what you did. You felt like every conversation was a mine field, and saying the wrong thing would cause everything to go to shit. That kinda stunted your relationship since then and... Wait... why do you hear her voice?