Beth and Brady

The Beth-Brady Relationship is the romantic relationship between Beth and Brady. It was highly doubtful that Brady even existed until The Aftermath: IV, when Brady showed up in person to see Beth.

Masters of Disasters
Beth mentions Brady and his many abilities during breakfast. When Heather and LeShawna point out that they have never heard of him before, Beth explains that she met him between seasons in the orthodontist's office when they were both getting their braces off. Beth pulls out a picture and reads his attribute written on the back. The picture turns out to be a model card, according to Justin. LeShawna adds her concern for Beth, asking why she's been chasing after another boy when Brady was back home, to which Beth replies that he's just a model but Justin is a supermodel. During the challenge, Beth continues to annoy her teammates with talk of Brady.

Ocean's Eight - Or Nine
Beth mentions Brady again, talking about his habit of constantly cracking his knuckles. Beth adds more detail to their first meeting. They were sitting in the dentist's office opposite to each other. She says that when she smiled at him, he thought she was making 'ouchy' faces due to being in pain because of the braces. According to Beth, Brady was eventually attracted to her from her perfume, Desperado: The Essence of Last Resort, which smells just like roasted chicken.

One Million Bucks, B.C.
Beth mentions Brady once more after she learns that Courtney is allowed to use personal devices. Stressing her anger, she complains, "I'm the one who has a boyfriend!"

Million Dollar Babies
Beth steals Courtney's PDA and mentions that Brady is going to be very happy when she talks to him (showing that he may be real considering she wouldn't e-mail a fake person). Later, when LeShawna accuses Beth of not having a boyfriend, she is very angered and shows an extreme amount of commitment to prove her wrong, winning her challenge for the Killer Grips. After LeShawna accuses Beth once more of Brady being "fake," then Beth proceeds to angrily tell her off.

Super Hero-ld
When Beth tries to convince Harold to vote off Duncan before the elimination ceremony started, Harold responded by saying "Tell me something I don't know." Beth takes this comment literally. She then responds to him by saying that Brady has two dogs, both named Steve.

Crouching Courtney, Hidden Owen
Courtney lets Beth use her PDA to call Brady, showing more proof that he exists, though she could have been faking it. While talking to each other, they tell each other to hang up first. They also kept saying, "I miss you more, no I miss you more," to each other, or at least Beth was.

Mutiny on the Soundstage
Despite supposedly breaking up with him two episodes ago Beth said she would either split the money with him or with Lindsay. She then says to Duncan she has a boyfriend, thought this may not be referring to him.

The Aftermath: IV
After Beth loses to Duncan, Brady is finally proven to be real when he shows up to be with Beth and the two embrace. She claims that she already had her prize, referring to her boyfriend. Then Brady only replayed by saying "Was I supposed to bring a gift?" In the alternate ending where Beth won over Duncan, Brady shows up to see her and the two embrace.

Evidence Against
Despite Brady being proven to exist in The Aftermath: IV, there have been a few moments that hinted he may not be real.

Beth and Justin
Beth's entire attraction to Justin goes against her relationship with Brady. Though she states that Justin is a supermodel, where as Brady is just a regular model, and that she can't help herself. However, around the time Beth began talking about Brady, she stopped falling for Justin's charm.

Masters of Disasters
Heather notices it is strange that Beth didn't tell anybody until that late in the season. Beth's only picture of Brady being a model comp card (which has information about the models on the back) was possible evidence against her relationship with him. This was also the first time he was mentioned, making his existence questionable due to him never being brought up by Beth prior.

2008: A Space Owen
In this episode, Beth begins to believe that Harold is crushing on her, even though he is not. She decides to break up with Brady and give Harold a chance. However, it is unknown how serious Beth was about the relationship with Harold, as it is only mentioned again in Mutiny on the Soundstage.

Mutiny on the Soundstage
While answering one of the trivia questions, Beth refers to Harold as "sweet Harold," indicating that she may still like Harold.

Trivia

 * This is the only relationship in which one member is not a competitor in the Total Drama Series unless you count Izzy's relationship with the Monster.
 * This is the second relationship to supposedly broken up to get back together and the third couple overall.
 * Both have used braces at some point in their life.