You mean 614? Because 100% is 615.
Anyway I'm assuming you mean 614 so that means you have one spot left. If you have one spot left then it's likely you've already cleared the Galeem, Darkhon, and Galeem & Darkhon spaces as it would be weird if you only done 2 of those and not 3.
If anything, I want to bet you're missing a fighter. And if I'm correct, I'm also willing to bet that it's Richter. If that's also right, then you need to wipe out every ghost in the Castlevania dungeon.
If I'm wrong then like others said, use the camera and look for every nook and cranny. Check to see the dungeons have a star on them in your map (the blue spaces meaning all spaces are clear). Also, check that one dungeon where you unlocked the path to go onto the bridge. I hear that it gives you a star if you cleared the FIRST floor, meaning it is possible that there can be a spirit left in the other floor.