Here's your scene expanded to ~1200 words, keeping your exact opening and closing lines:
After the fight, Jelo had had enough. He decided to call it a day and move on to the next part of his training — improving his firepower.
Originally, he had planned to play one more match. But after losing to Iron Fist, his morale was completely gone. The defeat lingered in his mind, making it impossible to focus on another fight. Instead, he logged off and decided to spend the rest of his time strengthening his abilities.
As he got up, he glanced to his right where Mira had been sitting earlier.
She wasn't there anymore.
She must have finished already, he thought. Probably went to do something else.
Jelo left the room and headed toward the academy's cafeteria, where students usually gathered to eat and relax. He hoped to find Atlas, Ken, or anyone who could help him with his training.
But when he arrived, the cafeteria was missing the faces he was looking for.
