I Used To Secretly Watch My Brother Masturbate, But I Think He Knew

A few years ago when we were teenagers My mom moved us into a new apartment with her new fiancee, me and my older brother. Shortly after we got settled in, I noticed that a vent in the upper corner of my room gave me a pretty clear view into my brother's room next door, provided that we both had our side of the vent open.

As a curious (and admittedly horny) young girl, I had some urges I'm not the most proud of. I fought the urge the first few days, but eventually the temptation was too much to resist and I started spying on him. More often than not, I wouldn't see much. His vent was usually only open about halfway making it difficult to get a good view. Still, I was able to catch frequent (albeit brief) glimpses of him changing or dropping his towel to get dressed after a shower. I also quickly learned that he had a habit of jerking off every night before going to sleep. I tried my best to watch each night, though sometimes it was difficult especially if his lights were off.

I want to mention that I never had any weird i****t fantasies leading up to this, and I certainly didn't think of my brother in a sexual way. He was objectively attractive if I'm being perfectly honest- played sports, was pretty fit, and his penis was definitely on the larger side. Nonetheless, I didn't see him "that" way. Yet still, the curiosity and the thrill of doing something 'taboo' was very arousing to me and I couldn't stop myself from looking.

This went on for a couple of weeks, but then things started to get more interesting. In hindsight, he must have known I was watching and enjoyed the attention, because he started to intentionally show off for me, or so it seemed. First of all, he started keeping his vent fully open pretty much all the time, giving me a much clearer view, as opposed to before where it would usually be only partially open if at all. Additionally, he started hanging out fully nude for extended periods of time, rather than just taking off one set of clothes and immediately changing into the next one like he used to. And of course, he started leaving the lights on every time he would jerk off. Though these changes did seem oddly convenient, I didn't question it much and just enjoyed it.

Then he started to take things even further. He spiced up his masturbation routine more with things he never used to do before. Like spitting into his hands or onto his penis rather than using lotion or going dry. He used to stay pretty quiet, but now would moan out loud and sometimes utter girls' names or certain words to give me an idea of what he was thinking about. He started occasionally sticking things in his butt, making him cum a lot harder. He used to always finish laying down and promptly clean himself off. But now, when it was time to finish, he'd get up, stand tall and wide in the dead center of the room and shoot his load right there on the floor- always facing right at me.

In hindsight, there's almost no way this was all a coincidence. He had to have known I was watching and went out of his way to put on a show. I'm ashamed to say I enjoyed every second of it at the time, I would even touch myself more often than not while watching.

We're a bit older now and although I think we both know what the other did, we've never spoken about it nor had any inappropriate physical contact. I just chalk it up to us being young, foolish and lured into sexual deviance by our crazy teen hormones. We have a perfectly normal brother sister relationship nowadays.