Logan Huntzberger is Rory's serious boyfriend.
Logan is the son of Mitchum Huntzberger, a successful newspaper magnate. Logan attended a variety of boarding schools in Massachusetts such as Groton, Rivers, Exeter, and Andover where it is presumed that he graduated. The Huntzberger family is what can be described as "old money". It is shown that his father loves Logan but at times treats him more like an heir than his son. His mother Shira tends to be snobby even though she doesn't come from "old money" herself. Logan and Rory met while attending Yale through Rory's friend Marty. Both Rory and Logan worked at the Yale Daily News, although Logan's appearance in the news room was uncommon and annoyed Doyle, the editor of the Yale Daily News every time he did bother to show up. Logan often refers to Rory as "Ace" because she wants to be a reporter. The nickname becomes a sweet term of endearment. Rory enlists Logan's help on a article for a secret society Logan was in called the Life and Death Brigade. Logan takes her to a secret event party in the woods (5.07).
Through that event, Rory becomes fascinated with the club and with Logan. She is convinced to take a dangerous jump with Logan. After this, Logan and Rory's paths cross more developing a tentative friendship with Logan comforting Rory at a party her grandparents threw for her where Dean broke up with her. Logan causes a fake fight for Rory as a prank but Rory gets him back by enlisting her grandfather to trick them into an engagement. Rory soon develops a crush on Logan and admits it at her grandparents vow renewal. Logan admits he likes her back but is not a commitment guy. Therefore, Rory and Logan agree to a no-strings relationship that lasts until mid S5 when Rory realizes that she can't do it and wants to be friends again. However, Logan takes it as a ultimatum and the two of them start dating. Rory is Logan's first serious girlfriend, except for when he was ten and claimed actress Alyssa Milano held the position, as revealed by his sister Honor. Rory and Logan's relationship survives many hurdles first his mother's and grandfather's disapproval of Rory because she wants to work instead of staying home and planning parties. However, Logan does not pay heed to what his family says and still stays with Rory. Logan also comforts Rory when his father says that Rory is not cut out to be a journalist. Logan supports Rory when she decides to take a break from Yale even though he believes that she will eventually come back to Yale.
Logan suffered a grievous injury during a trip with The Life and Death Brigade. Logan has been strongly encouraged, even forced, by his father to enter the family business.
At the end of season six, Logan moves to London to join his family business. Surprisingly, after the conflict he suffers with his father earlier, he takes his new responsibilities seriously, and does his job well.
Unfortunately, after he loses money after a badly thought-out investment in a new media company (the company violated another person's patent rights, and the third company waited until a larger company with deeper pockets bought it to sue for infringement), Logan regresses and acts irresponsibly once more by taking a trip to Vegas with Life and Death Brigade colleagues, Colin and Finn. He finally tells his father that he won't be part of the family business anymore, and starts to straighten out again.
After he gets an offer for a new job in California, Logan proposes to Rory. She considers, but turns him down, feeling she wants to accomplish other things first. She asks if they can continue their relationship in a long distance form but Logan decides that it would be too hard for him to continue seeing Rory after the proposal and after moving, he gives her an ultimatum, all or nothing. Rory decides that she can't do that so the heartbroken Logan breaks it off with her.