Blake Lively is gushing about her longtime friend Taylor Swift's music as her self-proclaimed biggest fan.

Blake Lively gushed about her longtime friend Taylor Swift's music as her self-proclaimed biggest fan.

When it comes to Taylor Swift's music, BFF Blake Lively knows it all too well. 

While the world-famous singer and adored actress have been friends for nearly a decade, Lively is admittedly also Swift's biggest fan.

"No, no, I really am," she reiterated to ET's Denny Directo during an interview at Book Bonanza in Texas on Friday. For the latest proof, look no further than the fact that Lively recently attended back-to-back Eras Tour shows... in Spain, no less. 

With both a general love for Swift's work and a very handy connection to the megawatt star, Lively helped secure her 2020 track, "my tears ricochet," for the trailer promoting the film adaptation of Colleen Hoover's It Ends With Us. 

"You could've put any song on, like, her music is just, like, unmatched," she gushed of Swift's discography. "Her writing is so beautiful and it's so personal and you can feel that, you can feel that in the way that she sings. You can feel that in her lyrics."

Blake Lively and Taylor Swift step out together in December 2023 for the singer's New York City birthday party. - Gotham/GC Images

As for the on-screen emotions, Lively has been tasked with conveying them as the movie's protagonist, Lily Bloom, who is suffering an abusive relationship. As an added pressure, the book has been a fan-favorite since its 2016 release with more than one million copies sold. 

"This story resonated with so many people, so there's a great responsibility -- I'm Spider-Man," she said with a laugh. "There's a great responsibility that comes with that... You want to honor this book and this character that people love so much, but you also want to bring a life and a humanity to it that is, you know, true to who you are, so it's just like a lot of different, you know, things that you want to accomplish in this story and I'm just so proud of this film."

Justin Baldoni and Blake Lively film for This Ends With Us. - Robert Kamau/GC Images

But will fans of the book feel the same? According to both Lively and Hoover, they certainly should. 

"Some people will always like a book better than a movie and some people like a movie better than the book, but I think that we just did our best to honor the book and honor the fans and I think really make something that, that works even by itself, like if you don't know the book, the movie works, and I don't think there's any way that if -- I don't believe that if you read the book and you saw the movie that you wouldn't be thrilled," Lively said. "We really worked hard on that, but I also believe if you saw the movie and then read the book, you wouldn't go, 'Hold on, this isn't'... I think they're both really beautiful."