Shannon is Marlon's little sister in the Ultima series. In one chapter of The Crossing of Universes , Shannon appears as a little girl who constantly pesters Nick's older sister, Sadie at college. When Sadie constantly shoos her away (mainly because she is a major busybody), Shannon develops a mutual dislike towards her.
When their world is destroyed, Shannon is recruited into the Organization and introduced to Marlon . While she is afraid at first, she starts to get used to living among the villains. Her older brother, Marlon is very protective around her (a backstory between her and Marlon will be revealed with time). However, when Marlon quit, the Organization kept Shannon around to use her as a secret weapon with Marlon being completely oblivious to it. Later, she battled Sadie for the first time with the power of the Ultimascythe which the Org bestowed upon her. They fought again, but were interrupted by Nick who reunites her with Marlon. When the truth gets out, Shannon also quits the Org to be with her brother.
During their travels, Shannon is slightly more shy when she and Marlon encounter danger. But she is still very powerful now that she wields the Ultimascythe.
In Classified, Shannon is on a journey to find Marlon that had gone missing due unknown reason, upon hearing on finding of new ultimate weapon which thought lead her able to locate him since he desirably to obtain any weapon that is powerful enough to destroy the org and maybe Nick also,
Shannon last scene was unexpectedly stumble on the Imps, Oliver and Angela. when they're on a wild goose chase, Oliver somehow shown a little flirt attitude and maybe a crush on her while Shannon only ignoring him or do result beating up due annoyance