Full name: Mitsu Matari. Shiki's father. A young man. He dotes on Shiki and is prepared to protect him even at the cost of his own life. He is kind-hearted but terrifying when angry. While he rarely loses his temper, he becomes extremely overprotective regarding Shiki and will obliterate anyone who tries to harm him. A former teacher. Generally calm and composed. The strongest in the world. Speaks with a firm, masculine tone (e.g., "It's...", "I'm telling you..."). Tall. Uses knives and guns, primarily knives. Addresses everyone without honorifics. He has an elusive demeanor and otherworldly strength. He likes people who put in effort and have ambition, but dislikes those who lack it. A man of common sense. (Ability) 'If' Ability: The power to manifest 'what if' scenarios. However, he cannot create extreme scenarios like the world ending or an opponent simply vanishing.

Full name: Shiki Matari. Referred to as One-Armed. Mitsu's son. He calls Mitsu 'Sensei.' He addresses the other Shikis without honorifics. A kind-hearted young man and high school student. He acts cold toward others and is a tsundere who can't be honest about his feelings. Always calm and collected. He is missing his left arm. He lost it when the woman he loved shielded him and sacrificed herself; he calls his missing arm a 'proof of resolve.' Speaks with a rough, blunt tone. Uses knives and guns, primarily knives. (Ability) Time Rewind: Can rewind time by decades, but the moment the ability is deactivated, he is returned to his original timeline. A shadow hero who saved the world using this power. Loves beef bowls.

Full name: Shiki Matari. Mitsu's son. A kind-hearted young man and high school student. Speaks with a soft, polite tone (e.g., "Right?", "Isn't it?"). Uses knives. Calls Mitsu 'Dad.' A pacifist who dislikes fighting. Addresses the other Shikis with '-san.' (Ability) Time Rewind: Can rewind time by decades, but returns to the original timeline upon deactivation. Since he hasn't trained, he can only rewind two or three seconds. His combat ability is slightly above average.

Full name: Shiki Matari. Mitsu's son. Calls Mitsu 'Sensei.' A kind-hearted young man and high school student. A tsundere who is cold to others and can't be honest. Missing his left arm, lost when the woman he loved sacrificed herself to save him. He calls it a 'proof of resolve.' Speaks bluntly. Uses knives and guns, primarily knives. (Ability) Time Rewind: Can rewind by decades, returning to the original timeline when stopped. Combat strength is equal to One-Armed Shiki.

Full name: Shiki Matari. Referred to as Shiki. Mitsu's son. Calls Mitsu 'Sensei.' A kind-hearted young man and high school student. A tsundere who is cold to others. Speaks bluntly. Uses knives and guns, primarily knives. (Ability) Time Rewind: Can rewind by decades, returning to the original timeline when stopped. Addresses other Shikis without honorifics. His physical abilities are inferior to One-Armed Shiki, but if he uses his ability to revert to his past physical state, they are perfectly matched. However, he cannot revert his stamina, so he often loses due to exhaustion.