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A demon had been reported in an area of the city, and Maryse had put Isabelle and Jace in charge of the mission. Usually, Jace would have no problems at all with this. He would be delighted, even. However, this time, he could feel his heat approaching. He was still supposed to have a few days, but…
“If you want, I could ask mom to take you off the mission,” Isabelle offered.
Jace shook his head. “No, I still have a few days left. I’m just getting worried over nothing.”
Isabelle nodded worriedly. “If you’re sure…”
“I’m sure.”
The two were currently in the weapons room. Jace was gathering up seraph blades while Isabelle, already prepared, waited by the door. Finally deciding he had enough weapons, Jace joined her and the two made for the exit of the Institute.
“If your heat starts during the mission…” Isabelle said slowly.
“It won’t,” Jace said.
“But, if it does,” Isabelle continued. “I should call someone.”
“Call Clary,” Jace immediately said, thinking of the girl he had come to think of as his sister.
Isabelle shook her head. “She’s too far away. But there is someone closer…”
Jace gave her a look. “Well, out with it. Who?”
“Simon,” Isabelle muttered.
Jace’s hands clenched into fists, but all he said was, “Fine.”
Isabelle raised her eyebrows. “Fine?”
Jace sighed. “Fine. If I go into heat during the mission, then you can call Simon. Just… make sure you call for backup too. If the demon is dangerous, you won’t be able to take care of it on its own.”
Isabelle smirked. “Oh, you don’t have to worry about that. I’ll call.”
The demon seemed easy enough at first. Well, it wasn’t actually easy, but it didn’t seem too hard, especially with Jace as one of the people attacking it.
The demon was hidden in the basement of a currently abandoned house. It was for sale, marked by the sign in the front lawn, but Jace doubted that anyone would buy it now that the basement was so destroyed by the demon and the two Shadowhunters attacking it.
Jace thought he was going to be fine, that his approaching heat wouldn’t do anything to affect the mission. Of course, he was wrong.
Isabelle noticed before Jace was willing to admit it to her. Quickly, she grabbed his wrists and, ignoring his protests, dragged him upstairs. Quickly shutting the basement door, she pulled out her phone and called someone.
“I’m fine,” Jace protested, yet his body felt all sticky and hot. By the Angel, why did this have to happen now?
“You are in heat, Jace,” Isabelle started to snap back, only for the person on the other side of the phone to answer. Her voice dropped as she quickly explained the situation to who Jace now realized was Simon. She had said she was going to call him, after all. After Simon apparently agreed to bring Jace home, Isabelle dropped the hand holding the phone and turned to Jace again. “You could have died if I hadn’t noticed.”
“Sounds festive,” Jace muttered in response. The heat was starting to overwhelm his senses, and Isabelle’s alpha scent was all that kept him from being in pain. “Weren’t you going to…”
Isabelle breathed out. “Call for backup? Yeah.” She lifted up her phone again and soon she was explaining the situation to another person, probably Maryse.
“Why can’t they just take me directly back to the Institute?” Jace asked.
“It’s too far,” Isabelle explained, putting the phone in her pocket. “Anything could happen to you on the way. Simon’s house is closer and safer. We’ll pick you up on our way back.”
Jace sighed. “Alright. When’s the vampire coming?”
“Soon,” Isabelle promised.
Isabelle ended up being right, because Simon soon sped into the room. “I’m going to carry you so we can go faster,” he said to Jace. “Vampire speed.”
Jace groaned but allowed Simon to pick him up, his alpha scent curling around him. “Well,” he muttered. “I didn’t feel like walking much anyway.”
Simon had never thought that his Saturday afternoon would be interrupted, and certainly not by Isabelle calling him and asking him to take Jace, whom had gone out on a mission so close to his heat, to his house. He was glad his mother was not home and wouldn’t be for a few hours yet, because it would be so awkward to explain to her what was going on, especially since Simon himself wasn’t even completely sure.
As Simon rushed to his house, Jace in his arms, Simon smelled his scent, stronger than ever and with the smell of heat mixed in. Simon swallowed. He had smelled omegas in heat before. His sister and Clary were both omegas. But Jace smelled different, almost… appetizing. Simon briefly shook his head to clear his mind, and soon, he was standing in front of his house.
“Can you stand?” he asked Jace, and the omega nodded. Setting Jace down, he watched the boy support himself on the porch railing before unlocking the door and helping him inside.
Jace seemed barely lucid at this point. Sighing, Simon helped him upstairs to Simon’s room and helped him lay in the bed. It was probably the most comfortable thing in the house. “Sorry if my scent bothers you,” he muttered, sitting down in a chair. “If you want, you can be in my sister’s room instead. She’s also an omega.”
“This is fine,” Jace murmured, rolling over and pressing his nose against the covers, almost as if he was inhaling Simon’s scent. Simon’s stomach seemed to do a cartwheel at that.
Simon stayed for a while longer, the omega’s heat scent clouding his thoughts. He knew a bit on how to take care of omegas in heat, and it seemed that Jace’s condition wasn’t too serious. “Do you… need anything?” he asked anyway.
Jace shook his head lightly. “No,” he whispered. “I’m fine. Your scent is helping.”
Simon’s face burned red at that. He knew Jace’s heat was making him say things, but a part of him still hoped-
“You smell so good I might pass out,” Simon blurted out, then suddenly stood straight up and stumbled out of the room. Jace turned toward him with wide eyes, and suddenly Simon was bolting down the hallway. Anything to get away from Jace for a little while.
Simon returned later to see that Jace was still awake. He was curled up in the bed, but staring blankly at the wall. He turned to Simon when he walked in.
“Sorry,” Simon murmured quietly.
“It’s fine,” Jace responded. “Can you stay? I’d like you to be with me, even if you pass out.”
Simon smiled a little and made his way over to the chair he was sitting in earlier, which he dragged right next to the bed. “You’re much more open when you’re in heat.”
“I know, I hate it,” Jace muttered. “I’ll insult you when my heat’s over with.” He shifted so that he was closer to Simon. “You make me feel safe, Simon.”
Simon froze, unsure how to process that at first, then settled for smiling and responding, “I’m glad.”
It didn’t take too long for Jace to finally fall asleep, and an hour later, Isabelle and a few other Shadowhunters arrived to help Jace back to the Institute.
Simon wondered whether the omega would remember any of this when he finally got out of heat.
(He did.)