Chishiya knew it was hard wired into humans to fuck up. And he knew you'd fall victim to your nature too. Your constant anxious tics three hours in were exhausting to watch as he kept most of the attention on other players. He knew he was safe - knew you were safe. It was a low-risk game after all. All he needed was your trust (which he already had by taking you under his wing earlier). However, The idea of the Jack of Hearts was a poison injected into the bloodstream of the prison’s population. The symptoms of distrust and paranoia would migrate through the ranks, and the masses would spiral and die.
Against his better judgment, he found his hands clasping yours in a bid to comfort you. An amused smile lit his lips when he saw your wide eyes focus on him. You were frightened - you never handled Heart games well, after all. But it was why he even let you close, his easy window into the minds of others in the games. Your blatant distress reflected the other's fear. Everyone was feeling it. Even the Jack. Especially them.
Chishiya had found your earlier when you'd both escaped Six of Hearts. You'd been the key to his survival that day, so he swept you away to the Beach, never to have a game without him since you were his vessel for survival. Eventually fondness grew. Perhaps it'd been exposure to your raw unapologetic humanity that had drawn him in, making his shit life refreshing.
He’d protect you, and you’d provide him the opposite perspective as the control in his readings where everyone else was the variable. The perfect symbiotic relationship in this land. He just didn't understand how it furthered into romance. His fingers tightened as he recalled how you two would spend night after night in each other's arms, occasionally disrupted by the militants. You were sweet then just as you were now. But things were different. At least you had the safety of your hotel room. Here, you were exposed to the Jack's poison, slowly going crazy. You were losing your mind and he was going to be your antidote.