Mark Sloan was one of the peripheral characters in the hit medical drama Grey's Anatomy, He first appeared on the scene as a fourth angle to the turbulent love triangle involving Derek, Meredith, and Addison.

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Mark's romance with Lexie or the lack thereof would always remain one of the most beloved storylines, etched in the minds of fans. The writers barely scratched the surface of the character but there were times when Mark, with his arrogant good looks, got away with things that were quite shameful. However, there were also times where Mark committed some selfless and kind-hearted deeds that he could easily take pride in.

Ashamed: Insulting His Interns

Mark Sloan looking serious on Grey's Anatomy

Mark was rather brash when it came to dealing with underlings, at least in the beginning when he joined Seattle Grace. He was a hotshot, incredibly handsome plastic surgeon at the top of his profession, so perhaps he considered himself entitled to being insolent towards the interns, who were, as Bailey had so aptly put it in the pilot, 'the bottom of the surgical food chain.'

Mark made his interns run around, serve him coffee, and generally gave them a hard time, not being much of a mentor to any of them, until Jackson Avery caught his eye.

Proud: Saving Alex's Life

Mark Sloan on Grey's Anatomy

Mark and Lexie's story is one of the most tragic love stories in the history of Grey's Anatomy. The two cared for each other deeply but somehow their choices drove them further away from each other.

There was a time when Lexie was with Alex after she had broken up with Mark, although she still obviously loved him. At this time, the hospital shooting of season 6 happened and Alex was found to have been shot, bleeding in the elevator. At this time, Mark's efforts practically saved Alex's life. He was aware of Lexie's relationship with him, but instead of letting his feelings cloud his judgment, he chose to save the man the love of his life was currently dating.

Ashamed: His Treatment Towards The Nurses

Meredith pointing a finger at Mark in elevator

Mark went on a massive rebound trip after Addison had left Seattle. He had sex with almost every nurse, intern, and resident in the hospital and generally gained some notoriety amongst the women for his behavior. The nurses' union even went to the extent of calling a strike and made complaints against Sloan due to the string of broken hearts he had left behind.

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Now, he was, sure enough, dealing with some heartbreak of his own since he had truly been in love with Addison. In addition, he was probably a very lonely man, with no real friends in Seattle, except for Derek who wasn't on the best of terms with him for a long time. Whatever be the reason, Mark slept around shamelessly, hurting women left, right, and center.

Proud: Taking Jackson Under His Wing

Jeese Williams and Eric Dane

Alex wasn't the only one of Lexie's flings that Mark took an interest in. When he realized that Jackson Avery was with Lexie, he decided to take a resident seriously for once. It was Mark who mentored Jackson and made him into the excellent plastic surgeon he became.

Mark realized Jackson's potential and kept at it until the latter grew a genuine interest in plastics and chose it as his specialty. It was nice of Mark to train Jackson and he would indeed have been proud to see his mentee had he been alive.

Ashamed: Stealing Bailey's Brain Wave For His Own

Miranda Bailey and Mark Sloan

When the hospital was abuzz with the race for the new Chief of Surgery after Richard chose to step down, most of the attendings prepared their own pitches to impress the panel.

However, Mark took the cake and won some brownie points with the board albeit for a short while when he impressed them with the plans that the hospital needed right then instead of in ten years' time. As it happened, this was something Bailey had told him and he rather callously pitched it as his own.

Proud: Never Shying Away From Having A Family

Callie and Mark in Grey's Anatomy

Mark might have been known for his extra-curricular activities but he was never afraid of real commitment when it came to starting a family.

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Whether it was his grown-up daughter, Sloan Riley, her baby, or his and Callie's daughter, Mark never shied away from the prospect of having someone to take care of. Even before that, he had been excited when Addison got pregnant and was deeply hurt when the latter chose to have an abortion. No matter the situation, Mark was ready to take up the responsibility each time.

Ashamed: Sleeping With His Best Friend's Sister-in-Law

Mark and Lexie looking serious on Grey's Anatomy

At the beginning of season 5, Mark and Lexie Grey were seen to engage in a forbidden romance after Derek had expressly told him not to. Of course, Mark was actually in love with Lexie, but even then, he had already done the exact opposite of what his best friend had asked of him.

Lexie was Meredith's half-sister and hence Derek's sister-in-law. And it would have been embarrassing for Derek if Mark had slept with her and simply moved on as was his nature. Of course, it was Lexie who often instigated the breakups with Mark, but nevertheless, Mark hadn't respected his friend's request.

Proud: Helping Callie Through Her Issues

Mark and Callie dancing and laughing in Grey's Anatomy

Mark was always there for Callie. When Callie agreed to move to Africa with Arizona, it was Mark who pointed out to her that she seemed to be making a life-changing decision based on what her girlfriend wanted and not what she herself desired. Of course, Mark went about it with his own rather uncomfortable plastic surgery metaphors, but he had a point.

Moreover, Mark was there for Callie and Arizona as the two dealt with their issues, even walking Callie down the aisle during her wedding so he was definitely a good friend to the couple.

Ashamed: Betraying Derek

Mark Sloan and Addison Montgomery in Grey's Anatomy

Mark's affair with Addison was probably the worst thing he did and hence his least proud moment.

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Addison was Derek's wife of ten years and Derek was almost like a brother to Mark. The two had even grown up together, so for Mark to sleep with her was rather despicable. He did indeed love her, but from Derek's perspective, this was the ultimate betrayal and Mark couldn't have stooped lower.

Proud: Coping With A Difficult Childhood

Mark Sloan was closed up about his own life and his past but it was revealed that he had had a difficult childhood with parents, who were emotionally disconnected. He had spent quite some time on his own and was a lonely kid until Derek's mother invited him into the family fold.

Given that, Mark must have been proud to have become a top surgeon, having overcome any emotional vacuum he might have experienced as a young boy. He was still a lonely man, a gap he probably tried to fill with as many women as possible. But he was also accomplished and sought after, which was something to be proud of.

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