I love these two nerdssssssss. Also I haven't read any of the Tales from the Shadowhunter Academy bc I'm waiting for it to come out as a book, so sorry if something in this isn't canonically accurate. :)
And I still don't own TMI.
12+17. Kiss on the nose+Shy kiss - Simon/Isabelle
When Isabelle leaped backwards from the last demon, seraph blade gleaming in the darkness and the dust that the demon left behind, Simon had absolutely no idea what to say. This was the first time he had seen her fight demons since he regained his memories—or some of them, anyway—and she was… she was… "Insane," he blurted out. "That was insane, you're insane—um, I mean that in the best possible way."
Isabelle threw her head back and laughed, even while she wiped the demon's blood off on the grass. "Aw, Simon, I know you do," she said, her dark eyes gleaming in the light of her blade. "Thanks."
"But I—I—" Simon tried to find the words and eventually settled on, "You'reamazing, and I'm so ordinary."
Isabelle had been scanning the gloom for signs of other demons, but at his words, she whipped her head back around and frowned. "You're far from ordinary, Simon Lewis. You were a mortal who knew about Shadowhunters, then a vampire, then a Daylighter, then my boyfriend—and the fact that you survived that is impressive in and of itself—and then you gave it all up to save us, and now you're going to be a Shadowhunter yourself." She sheathed her blade and took his hands. "You're not ordinary, Simon. You're a hero."
Even if he didn't quite believe those words—not yet—Simon knew an opportunity when he saw one. Careful, nervous, and afraid to make eye contact while he moved, Simon leaned forward and kissed her nose. "Thanks for that, Izzy," he said. "Hopefully, I'll be able to live up to your opinion of me someday."
Isabelle rolled her eyes and pulled him down for a real kiss, one that left Simon's ears ringing and his heart pounding. "That's what you don't get, Simon. You already have."