Trevor is an NPC in the Second Sea. He can be found inside of Don Swan's Mansion, near the pool. He is a key NPC to gaining access to the Don Swan boss.
Trevor wants a physical fruit that has a value of 
1,000,000 or above. In order to give him a fruit, the player needs to be at least Lv. 1000, if the player is not, the dialogue "Get out of here before I kill you" will trigger.
If the player gives Trevor a physical fruit of the appropriate value, he will take the player's fruit, and the dialogue "This is an excellent fruit, You may now speak to Swan." will trigger, and the player will gain permanent access to the room that Don Swan is in.
If the player gives Trevor a physical fruit that is not of the appropriate value, he will take the player's fruit, and the dialogue "This fruit is garbage, but I'll take it anyways." will trigger, and the player will not gain access to the room that Don Swan is in.
To give Trevor a fruit, they must unstore the fruit and talk to him.