Vacuum-Vacuum Fruit / Vac-Vac Fruit. Paramecia.
This fruit turns the user into a human vacuum, allowing them to inhale and exhale gusts of wind at inhuman levels, and allows them to store inhaled objects in their body until they are exhaled. They can also form holes in their hands and feet that are granted the same properties as their mouth. Stored objects are held within a sort of "hammerspace", allowing for the inhaling of a number of sizable objects, even if the user's body isn't logically large enough to hold them. There is a limit to the size and number of objects a user can absorb, but those limits depend on the user's strength and skill with the fruit.
The fruit has many practical combat and supportive uses. For instance, they can use it in battle by inhaling and exhaling large gusts of wind from either their mouth, hands or feet. They could also charge up wind blasts, pressurizing them until they are exhaled as "Coup de Vent" like air bullets. Another usage would be releasing strong gusts of wind from their feet, allowing for short bursts of speed or even flight. A user could even store hazardous items inside of their body, such as steel balls and swords, and exhale them out at opponents during battle, catching them off guard.
Whenever the user has an item that they need to keep safe or hidden, the Vac-Vac Fruit could be extremely helpful, as the item could be stored within their body and could only be aquired by beating it out of the user through force, or if the user reliquished said item and exhaled it. This power could be used to store a human, but only after becoming skilled with it. They would only be able to last in the "hammerspace" for a limited time, as it is essentially a vacuum within there, unless the user is constantly resupplying the stored human with inhaled gusts of air.