SUMMARY: Seamus had known he was gay from the first time he knew what it meant. The hard part was stopping himself from showing his crushes on attractive male professors. Seamus/Gilderoy one-sided.
Seamus wasn't sure what to do. He had had crushes before, he knew this much, and he also knew how to hide these little crushes. It came with the territory of being gay and sharing a room with four other guys for most of the year.
He could certainly admit when a bloke was good looking. Take Harry for an example, if he cleaned himself up a bit, he'd be smoking hot in a couple of years. He could even admit that some older guys were attractive. Ron's older brother Charlie is a fantastic example of that.
He had such success in hiding his crushes from the other blokes because they didn't expect any romantic feelings to come from him. Whereas, with his current crush, he didn't think he'd have the same success. His current crush? Professor Gilderoy Lockhart.
Professor Lockhart had everything that Seamus could ever want. He was older, so he could provide. He was hotter than a dragon's fire breath. All blonde hair and blue eyes. And deep down, Seamus did know that it was a silly crush, and that nothing would come from it; he truly knew that. But it didn't make a difference to the second year boy. He liked him regardless.
Seamus noticed everything that the older male did, and his grades in DADA were suffering. He could only focus on the movements of the Professor's body, rather than what he was saying.
No matter how silly it was, Seamus couldn't help but slowly fall in love with the blonde teacher.
Seamus knew that Professor Lockhart wouldn't last longer than the year, and that's when he'd try to focus on another bloke that might take his fancy.