James was approaching Lily, who was sitting next to Remus. They were having a private conversation about tweaking the Incarcerous spell to make it chains instead of rope. They had decided that if Severus couldn’t help them, they would try to do it themselves. So, they had hired many books from the library on the subject and were sitting at the study tables in the common room.

He had that look on his face, and kept touching his hair. Lily knew what he was about to do. Plus, Remus had warned her.

As he got closer, Remus chuckled under his breath, interested to see what would happen. But it never did. Lily had shot a jinx under the table, a silent jinx, which hit James and he toppled over.
“Jelly Legs!” Sirius said, falling to the ground laughing at his best friend.
Remus even tipped his head backwards and started laughing. Soon enough, the whole common room was alive with laughing. James couldn’t even get up; so Remus shot the counter-curse, much to Lily and Sirius’ disappointment. James got up, and said “See you later Evans,” and walked away.
“New plan,” warned Remus.