Despite being from the same Game, Sayaka and Celestia never interacted, due Sayaka's early death, altough both weren't seen to be on bad terms with each other. The two also share no events in the Ultimate Talent Develpoment Plan.
The only thing that both have in common is that both sacrificed a lot for their dream's, while Sayaka tried to kill Leon Kuwata, to escape the Killing Game, to keep on her dream as Ultimate Pop Sensation, Celestia, helped Hifumi to kill Ishimaru, too then kill the latter one, to fulfill her big dream, to live in a Castle with handsome servants. Personality-wise, Celestia and Sayaka have nothing in common, Celestia, is cold, and hiding her emotion's with a smile, while Sayaka has a nice personality and is always friendly.
Celesaya is a rare-pair among the Danganronpa, while having a decent anmount of fan arts and fanfictions on Archive Of Our Own, It's nowhere as popular as, Celestia and Sayaka's main ships, such as Celesgiri for Celestia and Ikuzono for Sayaka. Nonetheless some people still ship them and wish that Celestia and Sayaka would have interacted more with each other. Celesaya is often potrayed in fanfictions as a one-sided crush from Sayaka's side, due her being the nice and caring one.
In Celesaya fan arts, Sayaka and Celestia are often seen to have Tea togehter, or Celestia and Sayaka are togehter in their Sports Uniform. Often Kyoko Kirigiri is also potrayed on fan arts. Creating a poly ship between all three, since Kirizono and Celesgiri are decently popular ships in the fandom. A main reason why the ship sailed was because of the Opposites Attract Trope, which is a fairly popular trope, since Sayaka is nice and has a bubbly personality, and Celestia is rather cold, they perfectly match in this trope.
On AO3, the ship currently has 38+ works.
- Celesgirizono refers to the ship between the two and Kyoko Kirigiri.
- Class 78th refers to the ship between the two and the other students of Class 78th.