Horoka Isazuki is a senior at Hope's Peak High and is the Pactbearer of Determination. She is known to be determined, strong-minded, comical-like, energetic, repulsive, stubborn, and ignorant. Horoka has always been the carefree and cheerful girl who loves to help others and not herself, and never gives up despite the circumstances. However, she can also be extremely stubborn, often relying in her own strength to accomplish safety and justice for others. And it only got worse when her objective as a member of the student council is to eliminate any Pactbearers alive and running. And her first resort of such is to kill them, all-be-it in a more cheerful way and heroic-like. She easily takes pride in her work, feeling like a real superhero. When she heard about the HPC being Pactbearers, she first finds whoever is a member of it, believing that they are all evil. She tries to make quick work with Railo when he was pursuing Cairo Dory, Pactbearer of Wrath. And despite Railo and his current partner (whichever one) tries to reason her and explain what pact they forged, she refused to listen, believing that they are just making excuses. She almost succeeds into killing Railo thanks to her training as a martial artist and, dramatically, states that the Pactbearer of Vanity will no longer use his pride to hurt the innocent. But just as she was about to make the final blow, Railo told her the true meaning of his role as the Pactbearer of Vanity: when a person is utterly worthless and futile. Horoka pauses and sees who the Pactbearer was, and the two clicked in her head. Railo's partner would then tell them the rightful means of their title as Pactbearer and what they represent. Spirit-broken and discouraged, she retrieves her fist and slowly walks back out of the mist. Horoka would be seen again. This time she offers her assistance and had forged a pact with Demeter, the Monark of Determination, to defeat the Pactbearer of Discouragement. When freeing the Pactbearer from his will, she encourages him to not give up on what he was doing right and giving him helpful advice. Since then, Horoka became more careful with her perspective and now not only wants to reach out to the defenseless and needy, but also the broken-hearted villains who is having a hard time with their pain. She also forged a bond with Railo that can never be broken.