Soma is a male character with blonde hair. He serves as Popo's best friend while simultaneously harboring envy over Popo's status as the Guardian of the Forest. He perceives himself as physically and mentally superior to Popo, fueling a competitive rivalry. His attire includes a shirt and pants, along with a small tunic used to carry his arrows.

Soma's relationship with Popo becomes increasingly antagonistic as his jealousy intensifies. This culminates in his decision to align himself with the antagonist Adder after Chouk, one of Adder's associates, reveals herself as his mother. Fighting alongside Chouk, Soma actively opposes Popo, employing a flying Giraffe Stag Beetle in battle.

His allegiance shifts further into darkness upon the revelation that another of Adder's followers, Diuk, is his father. This discovery traumatizes Soma, driving him into a fierce battle against Popo within the fossil forest. During this confrontation, Soma suffers life-threatening injuries from an explosion. He narrowly avoids death when Serán, having evolved into a more powerful form, uses her healing abilities to save him.

Following this near-fatal encounter, Soma abandons Adder's faction and rejoins Popo's group. He develops profound hatred towards Diuk, his father, marking a significant shift in his motivations. Despite his earlier betrayal, he reconciles with Popo and fights alongside him using his Giraffe Stag Beetle companion.