So you want to get the secret kinitoPET ending? There are 10000 different guides out there so I'm glad you stumbled upon this one! Anyway, enough with the yapping, let me explain how to do this.

Step 1. You need to beat the game at least once. It doesn't matter if you choose to stay with kinito or not, once you do this, you will get 2 things: A chapter select, (not important right now) and a lense application, (important!!!!)
Double click the lense app to open it and it should just be a clear rectangle with the white bar on top. Just move the white bar around a bit and you might see these floppy disks/ black rectangles. These are part of step 2

Take your lense app and move it around until you find the floppy disk. It should be there. (By the way, this is done at the start of the game) You can basically ignore kinito and just keep looking, as there are 5 different floppy disks that you need to click on. (Only visible with the lense app!) Enter the web world and complete Sam and Jades minigames as usual.

Step 3, before you go to kinitos treehouse to play hide and seek, you have to go to the fountain in the middle of the web world. So once you are at that fountain, double click on it, (lense app might come up when you do that, so it might take a couple tries) keep clicking until it plays a small animation, (two top halves of the fountain will come apart and fall but get replaced by 2 more halves) then, instead of going to the treehouse, find the rope in the top right section of the web world, and click on it. It should bring you to a dark place. Make sure you have your files open, because those floppy disks you collected will give you a file each. Drag and drop each file into the dark world. It might take a few tries but an animation will play and after it's over your file will be decrypted. Do this with all 5 files.

Exit the game and reopen it and just keep playing it until you make it to the section where kinito pet asks you to give him access to the computer. Instead of putting in the code he asks you to, enter delete_all. The computer will ask you to enter all the codes you just got. When you finish, kinitoPET will be deleted! You will get the Bliss achievement. (Sadly, it's not rare)

If you are too lazy to do the whole floppy disk thing, here are the codes.
1. sonny_c
2. kinito_2dce9
3. hello_world123
4. 9ca181f338144c0
5. 963277d837457116a679ae1a7

WARNING! Some of these codes will be different for different games, but some, like sonny_c, will remain the same.

Ok bye