If you ask a casual Cobra Kai viewer if Demetri and Eli are brothers, you’ll probably get a confident “yes.” Making this assumption is simple. They use the same inside jokes, complete each other’s sentences, and refer to themselves as “binary brothers.” However, the short answer is no. They are not blood relatives. They have been best friends since kindergarten and have never truly let go of one another.
When you consider how the show presents them, the confusion becomes clear. At the lunch tables at West Valley High, Demetri and Eli are two misfits waiting for Kyler to start bullying them again. The quick-witted, sarcastic coder is Demetri. Eli used to be quieter when he was still going by his given name, and the scar from his cleft lip surgery makes him a target all the time. They even have a little song about being “one or a zero.” With a friend, who does that? It’s easy to understand why viewers read it as family because it’s the kind of private language that siblings typically develop.
| Detail | Information |
|---|---|
| Show | Cobra Kai |
| Are Demetri and Eli related? | No, they are not biologically related |
| Their relationship | Best friends, often described as “brother figures” |
| Nickname for their bond | “Binary Brothers” |
| How long they’ve known each other | Since kindergarten |
| Demetri’s full name | Demetri Alexopoulos |
| Played by (Demetri) | Gianni DeCenzo |
| Eli’s full name | Eli Moskowitz, also known as “Hawk” |
| Played by (Eli) | Jacob Bertrand |
| Shared interests | Coding, Dungeons & Dragons, Doctor Who |
| First friend they made together | Miguel Diaz |
| Common bully | Kyler Park |
| Dojos joined | Demetri: Cobra Kai (briefly), Miyagi-Do. Eli: Cobra Kai, Eagle Fang, Miyagi-Do |
| Biggest conflict | Eli breaks Demetri’s arm during the arcade fight in Season 3 |
| Turning point | Eli defects from Cobra Kai during the LaRusso house fight to save Demetri |
| Later rift | Disagreement over MIT applications in Season 6 |
| Where they end up | Both attend Caltech together |
Everything changes when Miguel takes a seat beside them. Eli decides he wants that kind of power, Miguel retaliates against Kyler, and Demetri follows him into Cobra Kai primarily to watch over his friend. That particular detail speaks volumes. Demetri had no interest in karate. Eli was important to him. Demetri storms out in protest after Johnny Lawrence makes fun of Eli’s scar, but Eli stays. Although it’s a brief moment, it establishes the tone for the ensuing seasons.
The degree to which the show emphasizes their bond is what makes the question “are they related?” so enduring. Eli transforms into Hawk, gets a back tattoo, grows a mohawk, and begins to treat his oldest friend like a problem that needs to be solved. Things become ugly. Demetri kicks him through a glass wall during a school brawl, and Eli breaks Demetri’s arm in an arcade fight after being pressured by his Cobra Kai crowd. It’s difficult not to feel the weight of that as you watch it happen. Although friends frequently drift apart, this felt more like a family falling out, complete with long silences and guilt.
The repair work is equally instructive. Eli immediately switches sides when he sees Demetri in an arm lock during the LaRusso house fight. He apologizes and flips the man who is holding him. Really, no speech. Demetri shows up at Eli’s house with their old binary brothers video after he loses his mohawk and quits karate, reminding him that a haircut never defined him. Eli returns to the dojo. One could argue that the character was saved at that precise moment.
The tension feels more like sibling rivalry than rivalry, even when they fight once more in the final season over MIT vs. Caltech. According to Demetri, he does not wish to lose his best friend. He will always be his brother, according to Eli. You don’t say those things to someone you just like.
So, are Eli and Demetri related? Not biologically speaking, and the show never implies otherwise. However, fan wikis frequently refer to Demetri as Eli’s “brother figure,” and that description seems to be accurate. There are relationships that don’t require a common last name. It’s hard to imagine one without the other by the time they leave for Caltech together, which could be the reason why so many people believe they must be related.
