A slow project with no start and end, just a character development.
Perennial (adj., not comparable)
- Lasting or remaining active throughout the year, or all the time.
- (botany, of a plant) Having a life cycle of more than two years.
- (figuratively) Continuing without cessation or intermission; perpetual; permanent; unceasing; never failing. [
- (figuratively) Enduring; lasting; timeless.
- (figuratively) Recurrent; appearing or recurring again and again.