Amazing game, sound effects, music, core mechanic and level design.
First I one this one major bug where you can fly and cheese some level like level 3 I think.
You can put the portal in the air (Jump -> wait to reach the max height -> press e) now you just need to Jump and immediately press 'e' which won't reset the velocity, now wait to reach to max height -> press 'e' then repeat. Now you can infinitely fly.
I really like the portal mechanics, it reminds me of portals. But it is quite confusing at first. So I would suggest the earlier level to be more introduce to the portal mechanic, button and boxes.
The levels design are great, it's really rewarding to figure the puzzle out!
Sound effects are great and music are really a blast.
The art could be better in term of polishing(like UNITY PARTICLE SYSTEM) but I don't mind the polygon tomato.
Also the wall could be reskin I think.
Lastly I personally don't think this really fit the theme of 'failure' and play around with the 'tomato'. Tomato can just be literally anything else like a person and it wouldn't change a thing. If you say soft lock puzzle are way to express 'failure' then you could say darksoul game also fits because it hard, minecraft also fits because you can die, And pretty much any game can be fit with 'failure'. (I'm open for your ideas)
Overall solid game that need some polishing on the level design and physics.(You also can get stuck on the wall which I assume can be fix with unity physics material 2d (setting friction to 0)