Cosmo the Seedrian is an alien creature known as a Seedrian, and she also a character from the canon series of Sonic X. She is the younger child of Earthia and Lucas, and the older sister of Galaxina. Her family's status is unknown. She is Tails' original romantic interest, and as a result, formed a rivalry with Cream.


Early Life and Presumed Death

Cosmo was raised on a space colony, since her home planet was destroyed before she was born. She had escaped when the Metarex destroyed it, along with her family and people. Once escaping through a ship, she came to Mobius, and told them there she needed Sonic's help to return the Plant Eggs to thier rightful places, and they agreed.

While battling Dark Oak, Cosmo had fused with his planet state to weaken him, and Tails shot the planet, which would kill Dark Oak, but it killed Cosmo as well. Sonic had given Tails her seed, the only thing he found that was left of her. After they returned to Mobius, Tails had planted her seed, which has now grown into an unusually large flower bud. 

IncaIceBunny's Fanfictions

Sonic Fanfiction

Tails had planted Cosmo's seed in a flowerpot at his home, but strangely enough, it has grown into a very large flower bud. Could this mean Cosmo's return?

More coming soon!


There are some noticeable differences in Cosmo's personality in this universe compared to her canon counterpart.

Similarities to the Canon Counterpart

Cosmo can be a bit clumsy at times, making her somewhat accident prone.

Differences from the Canon Counterpart

Though Cosmo is kind most of the time, she is less gentle, sweet, and pacisfistic than her canon counterpart. This is most likely due to her rivalry with Cream.

Her self-esteem has risen noticeably since her previous life, but she is not self-centered.


Being part plant, Cosmo can empathize with plants, and judge their life state.

Cosmo can jump down from high places, using her skirt as a parachute.

Cosmo can make a force shield to defend herself and her friends, depending on how big she makes the force shield.


So far, her only known weakness is getting air-sick relatively easily. However, this does not mean she is an acrophobic.



Current Relatives

  • Lucas (Father, status unknown)
  • Earthia (Mother, most likely deceased)
  • Galaxina (Older sister, most likely deceased)

Future Relatives

  • Miles "Tails" Prower (Husband)
  • Scout Prower (Son)




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