College AU Shance where Shiro is still older than Lance (maybe he went to the military out of high school and a few years after the “accident” he decided he was ready to attend college), but Lance is the funny first year gen ed teacher with a buff attractive male student with a prosthetic arm and a cool scar across his face sitting in the front row, smiling at him. All semester said student sends him looks while he’s teaching and Lance thinks he’s gonna die from embarrassment every time he starts stuttering because of it. After the final exam, Shiro stays late so he can finally ask out Professor McClain (not that he hadn’t tried a few times before, but Lance was very strict on his “I don’t date students” rule - mostly just because he was scared of getting fired on his first year - though he’d definitely expressed interest) Lance accepts the date now that Shiro technically isn’t his student anymore. They end up going on a date (and maybe a little more than that), Lance quickly finds out he has a thing for Shiro calling him “Professor” in a low voice.
“Takashi?” Lance asks, taking roll on the first day.
“I actually go by Shiro. Takashi makes me feel like I’m in trouble.”
“Okay, Shiro it is. I’ll make sure to only call you Takashi when you’re in trouble,” Lance says, perhaps a bit too flirty.
“I’ll try to stay out of trouble then, professor,” Shiro winks, flirting back.
Lance realizes he’s got a long semester ahead of him.