Light gets a useless skill in a world where one wrong fruit kills you dead, then watches his childhood friend sprint past him toward legendary status. He doesn't get stronger faster or smarter or luckier. He gets better at eating poison. The show is about the specific kind of humiliation that comes from being left behind by someone you promised to match, and the only way forward is to swallow something that's supposed to kill you, over and over, until your body stops dying. That's the entire premise. That's the entire show. Every episode is Light choosing to eat another fruit because standing still while Rena becomes a legend is worse than the chance of getting erased.
Light wants to be the world's greatest adventurer, but his first skill pull is a dud. Fruitmaster sounds powerful until he learns the brutal truth: eat a second skill fruit and you're dead. Everyone gets one shot, one power, and that's it. So when his childhood friend Rena rockets to S Rank while Light spends his days farming and swinging a sword, the gap between them grows harder to swallow. Then Light makes a mistake that should kill him. He eats a second fruit. Then a third. Then another. Somehow, impossibly, he survives. What seemed like the worst skill in existence turns out to be the only one that matters: Light can consume unlimited skill fruits without consequence, stacking their powers with each bite. Now every fruit is his to claim, every ability within reach. The question isn't whether Light can catch up to Rena anymore. It's whether the world is ready for what happens when someone can become infinitely powerful and actually get back up to find out.