While Marissa easily won the competition with six votes to Ross' three, her decision to bring Ross to the final two stunned a lot of viewers.
"What's weird was, even Julie [Chen] was like, 'I can't believe you took Ross, that was such a bad choice," Marissa revealed to ET's Brice Sander after Sunday's live season finale. "My son and my husband were both like, 'Ah! Why did you that?'"
It was Marissa's choice to bring Ross -- arguably one of the most skilled contestants in the house when it came to manipulation and persuasion -- into the final two after she won the final Head of Household contest and evicted Mark McGrath and Ariadna Gutierrez.
Despite the possibility of losing, Marissa explained that she stuck with Ross because he was the reason she got as far as she did.
"I wouldn't have been where I was if I hadn't been playing with Ross," she shared. "Ross saved me, time after time. My alliance with Ross was the only real, true [alliance]. We had each other's back the whole time, and you have to trust somebody in the house, right? So I trusted him and he trusted me. So not taking him, to me, wasn't part of my spirit."
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"I'm a Big Brother fan and I know in Big Brother Land, yes, that was the worst move. But in my heart and in my soul -- and in being a mother -- [I wanted] to show [that] if you have a good friend, regardless of what the outcome is, you take your friend."
In the end, most of the jury agreed that while both Ross and Marissa had done their fair share of underhanded dealing, it was Ross who had burned the most bridges with how he played the game, and it was Marissa's dedication to their friendship that likely won her the $250,000 grand prize.
Ross may not have been crowned the winner, but he did snag the $50,000 runner-up prize and was voted America's Favorite Houseguest, which netted him an additional $25,000.
"I am so grateful for every single second in the house," Ross told ET on Sunday. "I am so happy... The fans of the show get this game -- how you have to play it, how the rules outside the world don't apply in the Big Brother house -- so I'm glad they got it."
For his part, Ross feels that he played the game the way it was supposed to be played, and the contestants on the jury who held it against him were letting their emotions get the better of them.
"I think the houseguests were kind of emotional about it all, but that's how it works. You go in the jury and you vote. This is the first time the jury actually got to see the show," Ross said. "But listen, I did something right! I got second place and America's Houseguest! I'll take it."
Ross also said that had he won the final HOH competition, the final two likely would have been the same.
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"It would've been a tough choice for me, because I think I could've done well against Mark, but I really wanted to be loyal to Marissa," Ross explained. "All the way through, Marissa and I were ride or dies, and we made it to the final two, and I'm thrilled for her that she won."
One of the highlights of Ross' time on the show actually came when he became something of an investigative journalist and managed to get Omarosa Manigault to candidly open up about her time in the White House, where she worked for President Donald Trump as a political aide.
"See, I didn't even know if that aired! Did that air? I deserve some sort of Pulitzer, right?!" joked Ross.
"I felt like you guys sent me there to get it out of her! So, I was on a mission," Ross said. "I'm so happy people saw that because I [was] getting stuff [from her] in the backyard going, 'This is gold! They better be putting this on the show!'"