|Famliglia Name||Shimon Famliglia|
|Current Boss||Enma Kozato|
|Affiliate Famiglias||Vongola Famiglia|
The Shimon Famliglia is a family that has been associated with the Vongola even before the time of Primo. However, as the family has gone from generation to generation it rapidly became a much smaller and weaker family, to the extent that Reborn with his extensive knowledge of the Mafia world, has never heard of them. The guardians used to attend Shimon Middle School but due to several natural disasters that moved to Namimori Middle School due to it's convenience of being invited to the Inheritance Ceremony which is being held close by. The 7 known members who the Famiglia were revealed to Tsuna when he interjected a fight between Kyoya Hibari and Adelheid Suzuki. According to Adelheid, the boss of the Shimon Famliglia is currently Enma Kozato.Reborn had suspicions about the Shimon Famiglia so requested that they worked close with the Vongola Famliglia so he could analyse them all individually. Adelheid remarked about the Vongola Sin and Kaoru dropped a parchment of paper with the crest of the Vongola crossed out in a thick marker and attacked Takeshi Yamamoto when he Timoteo had hidden the real Vongola Sin. Tsuna asked if Kaoru was responsible for Yamamoto being hospitalised, to which he replied with yes. Infuriating Tsuna.
Unlike the Vongola - who use the "The Seven Flames of Sky - The Shimon Famiglia have revealed that they use a unique flame type only exclusive to their family called "The Seven Flames of Earth".
The Shimon and the Vongola Family used to be very close back in the days of Primo. However Vongola planned to taking out every mafia family in Europe in order to rise to the rank of the most powerful Famiglia in the world and they wanted to use the Shimon Family as bait. Cozart, the first boss of Shimon, accepted only taking 50 family members with him to lure them out and were expected to go up against an army of 20,000. However, Shimon waited for rescue but none ever came resulting in the first boss to be ripped limb from limb whilst the other members met a merciless end, blaming the Primo for Cozart's death. After this the Shimon were looked down upon as criminals, a status that would last with them for an immeasurable time, losing all connections that had obtained with other Mafia families. The blood spilled from Cozart was bottled and became the "Vongola Sin".
 Known Members
- Cozart Shimon (Deceased)
- Enma Kozato (Current Boss)
- P. Shitt
- Adelheid Suzuki
- Kaoru Mizuno
- Rauji Ooyama
- Koyo Aoba
- Julie Katou
Koyo Aoba is the Forest Guardian of Shimon. With the self proclaimed title of "Hope of the Boxing World", he is an avid fan of boxing and shows himself to be extremely proefficient in the sport, being able to battle on par with Ryohei Sasagawa. Although not expessively shown, Koyo is actually extremely well built. When in battle he takes on a cocky demeanor due to the belief that with his abilities, he can win any battle. He has extremely sharp and agile reflexes, augmented speed, lightning-fast punches of which are powerful enough to break bones on contact. The threat he presents on field is further enhanced through the use of his Forest Flames, giving him the field advantage.
- They all have red eyes.
- It is unknown if they exist in the future because their powers were founded when Tsuna and the other returned from the future.