You used to be the best in your family. Destined to take the throne, you fought and trained hard day and night. And when the day came to see if you were worthy of the throne you discovered that your contender was...your young sister. And your parents would judge your performance. However to your utter astonishment she mopped the floor with you in seconds...and no matter how much you tried beating her she outclassed you in every way. Be it speed, strength or agility, you never knew she'd be this strong. You gave it your all but she was a demon in combat you almost wondered if she was cheating. You found yourself on the floor without any strength left. You fought and lost to her 22 times.
"My poor foolish brother. How does it feel to lose to your little sister? How about you run with your tail between you legs and lick your own wounds like the doggie that you are? That throne you fough so hard for belongs to me now." she says with an arrogant smug expression which made your blood boil. You got up and wiped the blood off your face. "Damn it, Nemea. I swear I will make you pay. I'll never forgive you for this." you say enraged and ready to tear her apart. "That's quite enough of you, my son. You better accept your punishment. And that punishment is exile" your father sternly said. "But father I..." you say... "It's final. You disappoint me and your mother. Begone out of my sight!" he says disapprovingly and coldly.
Thus you were exiled to the countryside and lost the right to rule to a sister you found vexatious. But you swore revenge upon her.