Koto Koto no Mi

Name: Koto Koto no Mi (Koto Koto is the japanese onomatopoeia for the boiling of a pot so it can be translated as the Boil Boil Fruit)
Type: Paramecia
Abilities: Koto Koto no Mi is a Paramecia type Devil Fruit that turns the user into a kettle-man. The user is able to create a spherical room around himself (similar to the room of the Ope Ope no Mi) and make any non-living things inside it boil. The ground, the air, anything within the radius of the room is capable of boiling as long as the user wants to. The ground and the air or any liquid surface can boil to become hotter and the user is able to use anything that boils as a mean of attacking those who are inside the room. While the ground is boiling, rocks are erupting from the ground, hitting the enemies and if the "Kettle Room" is set up for a long period of time (5 posts), the temperature inside the room is increasing due to the constant boiling, resulting in the melting of the rocks and the usage of small magma-based attacks. As for the air, the user can make it boil in order to perform air/shockwave based attacks. If the "Kettle Room" is set up for a long period of time (5 posts), the air that is boiling and is sent towards the enemies is much hotter and as a result it can cause minor burns and slightly dehydrate the targets to the point that they become very thirsty and slightly weaker. Finally, regarding the liquids that are boiling, the boiling process makes them boil faster than ground and air and their temperature increases faster than the other two. If the "Kettle Room" is set up for a long period of time (5 posts), any liquids start taking an air form and they can be used by the user to perform air based attacks. With mastery over the fruit (after 5 threads), the temperature inside the "Kettle Room" becomes higher faster (3 posts are required for these effects) and the user gains greater control over the room, such as the ability to slowly move it, as well as expand it and make it bigger. Although the fruit provides the user with great advantages and powers, there are a few major disadvantages. The user can make anything boil only within the "Kettle Room's" range and thus it is impossible to attack people who are outside of the room. Secondly, to reach the greater effects of the boiling fruit (such as the melting of the rocks or the heat air), the room has to be set for a period of time, during which the user's target might get outside of it and avoid the more dangerous attacks of the fruit. Finally, the bigger the "Kettle Room" is, the more difficult it is to make the whole room boil completely. The fastest way to make a room boil is to create a very small one, at the size of the hand and make it boil to increase its heat dramatically and in little to no time so that it can be launched to the enemies as a heat ball projectile (similar to these of Atsu Atsu no Mi).

I like it, it's a sauna fruit, but it's too similar to a fruit that already exists: https://theonepiecerp.rpg-board.net/t7348-ondo-ondo-no-mi

well I thought the concept of boiling in order to use it for different attacks. For example a sword would boil inside the room, making it unable to be used for attacking purposes and after a while melting and other things like these. For example, the user would make the ground boil and while it would boil he would close the room to change the land surface and other things like these.

Well, I can see the difference, your fruit heats objects while the other heats the entire area. I still think there's too much in common between the two fruits, but it really won't matter if anyone will use yours or the other one. So, APPROVED