Aden was born a Nightblood, he was brought to Polis with the other natblidas novitiates where he was taught how to fight and trained for the Conclave with the possibility of becoming the Commander.

Aden is briefly seen sparring with Lexa. Lexa praises him during their sparring session and later tells Titus that Aden was a better fighter than she was at his age.

When the rest of the Nightbloods are called away by Titus, Lexa calls Aden back to introduce him to Clarke. Lexa refers to him as the most promising of the Nightbloods and is confident that if she should die, her spirit would pick him to succeed her as the next Commander. Aden assures Clarke of the safety of her people if he becomes Commander.

Aden watches Lexa's fight with Roan along with the other Nightbloods. When the fight is over, Aden is relieved to see Lexa has survived.

After Titus accidentally killed Lexa Aden is seen conducting the purification ritual with the other natblidas before the conclave. Clarke comes to see him and asks him if he'll still support her people. He says he and the other nightbloods all will as Lexa made them vow it.

Aden appeared to be a polite, kind and genuine boy. Aden genuinely cares about Lexa, being very determined to keep his promise to her to protect the Sky People if he becomes Commander. He is also shown to have a protective side.

Aden was a scrawny young boy with messy, sandy blonde hair and blue eyes. He was average height for his age. He was usually seen wearing light armor consisting of a long sleeve black shirt, black pants, black boots, and a vest.

Aden had won the conclave and ended up with the Flame which gave him access to all knowledge wisdom and memories of the past Commanders

Aden woke up from reliving Lexa’s memories, it was strange, he wasn’t just seeing her memories he was living them, seeing them through her eyes, Aden was Lexa. Aden spoke in meditation Heda Leska kom Trikru I need you, please Heda Lexa help me understand what you’re trying to tell me.