(⋆. 𐙚) Urumi Aramaki!,

A 'visa' is a conditional authorization granted in order for people to stay in the Borderlands. Visas are granted to both players and Dealers through the games. As every day passes, the amount of visa remaining for a player reduces by 1 at midnight. If someone's visa hits 0 by midnight, that person is killed by the laser from the sky.

Urumi is a young woman with shoulder-length ginger hair, part of which she wears in 2 buns, and long bangs. Despite the dark and gloomy environment, she is seen in a long light blue dress in the Sweet Lolita style, which makes her appearance cute, childish and, most importantly, trustworthy. The dress is decorated with laces and a large ribbon bow at the chest. She also wears white socks and black boots. During the game, Urumi is often seen eating/carrying a lollipop or a Pocky stick.

Urumi appears to be a caring and cheerful person with a sweet tooth, which is highlighted by her appearance. However, as the game progresses, she reveals her manipulative and traitorous side, stopping at nothing to have other players act according to her wishes. She ends up being a cold-blooded murderer, who lies and kills people on false allegations without a slight hesitation and with a big smile on her face as she does so.

Urumi is first seen during the introduction of the Jack of Hearts game. Before Round 1, she suggests teaming up and telling each other symbols, and is happy to let anyone join. Walking by Ippei and Chishiya, she invites them as well, however, even though they agree, the duo stays away and does not participate in the group activities.

During Round 2, Urumi witnesses Akifumi Seto being bullied by Genki Kiryu, who wants to know his symbol, and invites Seto to the team.

After Kiryu's death due to Seto's lie, Urumi immediately turns on the latter, accusing him of being the Jack of Hearts and claiming that it is too dangerous to keep him alive even if he is not, which leads to the group lying and killing him. During the next round, she suggests getting rid of Meisa Tokui, who hesitated about eliminating Seto during the previous round.

Later, Urumi's treacherous behavior causes Shinobu Furuta to have doubts about the group and ask for a second opinion, despite Urumi telling her the truth about her mark, which then results in Furuta's death.

Urumi tells Aoki and Tomita to kill Kaneko Urumi tells Aoki and Tomita to kill Kaneko During Round 9, Urumi catches Motohiko Kaneko attempting to lie to her and suggests to Satomi Aoki and Hiroshi Tomita, the only two other surviving members of the group, that they need to have him killed. She remains oblivious to the fact that Kaneko suggests the same thing about her, due to her ruthless antics throughout the game. Upon witnessing Urumi and Kaneko still acting as a team, despite conspiring behind each other's backs, Aoki and Tomita decide to have them both killed. Urumi is told that her symbol is Spades, to which she reacts with "You are the only people I can trust!", and happily walks into a cell. She bites off her Pocky stick and names the mark, only to have her collar explode, causing her death.

Players have to guess the card suit symbol that appears on the back of their collar at the end of each round. Players may not bring in any reflective surfaces or materials. Before the game begins, a mark appears behind each player's collar, rendering everyone unable to see their own mark (Spades, Diamonds, Clubs, Hearts). Players are free to roam around and talk during the round. In the final five minutes of each round, players have to enter their cells and reveal their symbol. 3 actions are prohibited: No more than 1 person may reside inside a locked cell. Players may not obstruct other players from entering a cell. Players may not revoke another's ability to announce their own mark (homicide). It is GAME CLEAR for all remaining players after the Jack of Hearts dies. It is GAME OVER for the player if they attempt to cheat by using a reflective surface to see the symbol. It is GAME OVER for the player if they guess the symbol wrong or fail to give an answer. It is GAME OVER for the player if they use weapons or violence to kill other players. It is GAME OVER for the only person left alongside the Jack of Hearts.

In the prison, there are no reflective surfaces. All knives in the kitchen are ceramic, faucets dispense tomato juice, and there are no mirrors. Since the penitentiary is so large and spacious, it is subtly encouraged for players to have discreet conversations discussing claims and strategies.

Near the first few rounds of the game, 3 apparent factions begin to form: the group, partnered players, and loners. The loners are the first to gradually get eliminated. The group soon follows, as Urumi begins manipulating everyone to lie to those who have even the slightest suspicious tendencies. In the end, the partnered players are the ones who last the longest.

The most successful strategy is finding a partner and staying with them. Near the start, it is guaranteed both parties will only announce the correct mark, since lying would draw heavy suspicion. Near the end, should they trust each other enough, they would be able to deduce the identification of the Jack of Hearts from seeing who the final player is. Staying with a group seems to be the most practical option, but it would not last long due to how easily swayed people can be. Once 1 person has been killed in the group, then no one else in the group can be trusted, not alone or together. Going alone is suicide, especially towards the end of the game. Towards the end, a 4th faction forms. It is another group with Mitsurugi as its leader. His attempt is to drag the game out until the food runs out. Even if the Jack of Hearts is within the group, they could live in peace for half a year. However, Mitsurugi's attempt holds a massive flaw: this would kill the rest of the players outside the Solitary Confinement game within a month, as their visas expire with no means to clear the last game. Ōki eventually quells the group by tricking Kariya and shoving him into the same cell as Mitsurugi, knowing full well that only one person is allowed to be present in one cell at the same time. As stated by Urumi and Mitsurugi respectively, the longer the game goes on, the worse off it is for the players. Even if there seems to be nothing out of the ordinary, the Jack of Hearts is convenient and setting up their master plan from round 1.