|“||When this is over don’t remember this moment, remember the other ones. New Years Eve, champagne - your terrible, terrible guitar playing that never really got any better even though I said it did. And remember - I had over a century of pain and loneliness before I found you and then three glorious years of love. I love you.||”|
— Enzo to Bonnie in Gods and Monsters
Their relationship began in Total Eclipse of the Heart, when Enzo, who was working with Damon to track down the remaining Augustine members, decided that the best way to get Bonnie to help them find Wes was to threaten her boyfriend, Jeremy, with death. This set their relationship off to a rocky and antagonistic start, but they were ultimately able to set aside their dislike of each other to focus on bringing Enzo and many of Bonnie's friends back from the Other Side before its collapse.
In Season Seven, we see the pair in a romantic relationship, but in a flash forward, after Bonnie gets in trouble with the Armory, three years ago, and Enzo stepped up to keep them away from her. Enzo moves Bonnie up in a cabin, and over the years the two began to grow close. Two years later, after their romantic feelings had build up, the two started a romantic relationship and fell in love. After dating for three years however, they are currently separated due to the Armory's Monster mentally incapacitating him to do the creature's biding (along with Bonnie and Enzo's best friend, Damon). Bonnie, along with their friends, are currently trying to find and save Enzo and Damon from their mental hijacking by the Armory's unknown and mysterious creature.
They are known as "Bonenzo" or "Benzo" (unofficially) by fans.
Throughout The Vampire Diaries Series
In I'll Wed You in the Golden Summertime, Enzo is seen knocking at the door of the Salvatore boarding house. Bonnie is the one who answers the door only to close it immediately when she sees him. He holds it open and explains that he's there to visit Lily who must be lonely and hungry. When Bonnie refuses to let him in, he gives her an iPod, asking her to give it to Lily and telling her that it contains loads of songs from the last era she knew.
In Hello, Brother, the season opens up with revealing that it's been months since Bonnie has last been with Enzo. Bonnie and Stefan have been searching for Enzo and Damon for months while knowing that the Armory's monster was mentally controlling them. When they finally get another lead on them, Bonnie refuses to have hope on finding them, but Stefan convinces her to come along for searching their supposed location anyway.
When Bonnie and Stefan do find Enzo and Damon, they tell Bonnie and Stefan that it was a bad idea to find them. When Bonnie refuses to leave because of trying to find Enzo, this puts Stefan and Bonnie in more danger. When Enzo finally appears, Damon puts Bonnie into a chokehold, which she cannot defend herself against being she has no more magic. Stefan finally convinces Damon to let her go. Eventually, Bonnie and Stefan decide to leave, while leaving Enzo and Damon behind. After leaving them, Bonnie exclaims how Enzo was trying to help them with information regarding the creature from the vault. Bonnie now has hope again that she can rescue Enzo and Damon from the Armory's monster's clutches, which is later revealed to be a Siren.
- Enzo called Bonnie "little witch" multiple times.
- Michael Malarkey has shown interest in Bonenzo early this year, when Kat Graham had announced Bonnie would be getting a new love interest due to Jeremy leaving.
- The idea for a Bonnie/Enzo pairing began in I'll Wed You in the Golden Summertime when Enzo came to visit Lily at the Salvatore Mansion, where he was met at the door by Bonnie. “Kat [Graham] and Michael [Malarkey] had such … chemistry in that really short scene,” Dries recalls. “We were like, ‘Huh … Let’s explore that relationship.’ Of course, they have no reason to like each other; in the present day, we’ve been telling their hate story. So the whole point is that, when you see them in the future, you’re supposed to be like, ‘Wait, how did they get to there?’ Hopefully it created enough intrigue to keep [fans] guessing.”
- In Days of Future Past, it is revealed that Enzo has been giving Bonnie pills made out of Rayna Cruz's blood and it might be killing her.
- Plec promises fans will get to see how Bonnie and Enzo ended up in love over the missing three years, calling their relationship “lovely” and “beautiful.” This story was explored in Somebody That I Used to Know.
- In One Way or Another, Rayna Cruz confirmed Enzo loves Bonnie.
- As of Somebody That I Used to Know, Enzo is the second man that Bonnie has sex with.
- Bonnie has told Damon that she loves Enzo in Somebody That I Used to Know.
- Julie Plec on Bonnie and Enzo: "In the case of Bonnie and Enzo, we decided to show them in love with each other as a surprise flash-forward, leaving the audience to wonder how in the hell that happened. I really love the idea of them together. Enzo has so much love to give, but has been constantly disappointed by people in his life. Bonnie, always giving so much of herself to others, deserves the kind of love that is unconditional and powerful and selfless. I love them together." 
- Chris Grismer had the Billie Holiday song play out loud for the whole cast and crew while Kat and Michael danced. Everyone was so moved. One of the crew members came up to Holly Brix with tears in her eyes. She wanted Holly to know how much she loved seeing Bonnie get a epic love story.