Their voices can be annoying to listen to due to their mischievous personas. Especially when they talk at the same time.
Their alternate voice in the first Puyo Puyo Tetris game makes them sound too depressed rather than being pranksters.
They keep treating Ai like trash as they often prank on him too much such as lacing his dog food with spice, putting a bow on his tail, or even mock him to the point where Ai feels anxiety. Speaking of pranks, they for no reason keep doing pranks to the point that they are irritating.
Every time they lose a game of Puyo Puyo Tetris, they keep blaming each other for losing despite the fact that both are two in one character. It's like they both can't take the blame when they are losing. So with that said, both are at fault when it comes to losing as they are the ones who are two-in-one characters.
In Puyo Puyo Tetris, they have no clearly defined role in Starship Tetra and act more of an obstruction than anything else. It's almost like they have no purpose other than to prank. Even using the excuse "to l liven things up" isn't gonna work as they seem to be used to their shenanigans.
Their reason as to why they prank is just pathetic. Sure, them being lonely does make you feel bad for them, but there is a big impact that just feels not right. So in other words, why would they want to not be lonely if they constantly pull pranks? That would cause friendships to go downhill usually.
Speaking of treating others like trash, they even teased Ess at one point. Yes, they usually pick on Ai a lot, but still. Anyways, it may be true that Ess can be an immature crybaby and that she may deserve it, but Jay and Elle at one point mocked Ess for having feelings for Maguro.
They are basically Yu and Rei except unlike those two characters, Yu and Rei were more than a simple young duo. Yu is a cheerful ghost who had a dark vibe in her polar opposite prior to her ghost life. Rei is a quiet and terse character who was happier when he was alive. Jay and Elle on the other hand can't have the same thing as Yu and Rei. This makes Jay and Elle an expy of the previously mentioned characters.
Since they never get any comeuppance for pranking others, they can be considered Karma Houdinis.
Despite their pranks, they were concerned about Tee and O being warped away by Ex.
In Puyo Puyo Tetris 2, they were given roles as they have supernatural senses like being able to contact with each other like radar as it justifies their presence in the crew. If Tee is to be believed, they even saved the Starship Tetra many times.
Their character designs are cute.
Their voice actors still did a good job voicing them. Even if they are pretty irritating.
They are based on the J and L tetrominoes.
Since Jay and Elle are never referred to individually, their genders are never explicitly clarified. However, they are able to activate both Boys and Girls combinations in Puyo Puyo!! Quest, implying they are one male and female each. Due to their names and voices, it may be assumed that Jay is male and Elle is female.
Unlike other Tetris-based characters, Elle's color scheme does not exactly reference the Tetrimino they're based on. However, it may be said that their suit color is brown.
According to Utako Yoshino on a Tweet, they pull pranks due to them being very lonely.