A season is, on Everglow, one complete round of a story: a run of chapters with its own arc that ends at a point where something has been settled. The story can then continue in a new season with the same characters, who remember everything.
The word is borrowed from television, and the comparison holds. A series tells its story in arcs, each with its own ending. For romance that fits better than a book with a last page, because a love doesn't stop being interesting after the first kiss.
A season ends when the question it opened with has been answered. The guest has said why he extended his stay. The pact is fulfilled or broken. The characters stand at a new beginning rather than at the edge of a cliff.
Seasons make a story durable. You can stop after one round and feel finished, or start another and see what becomes of the two of you when ordinary life arrives. Everything that happened in the first season, the characters still know.
At Everglow you do not just read it. You are the protagonist, and every chapter ends with your move.