A 20-year-long career could make anyone feel old — so singer Younha is choosing to live like a 20-year-old instead, with her seventh full-length album, “Growth Theory.”

“Twenty years singing makes me sound like I’m a veteran, but a 20-year-old is so young and has so much ahead of them,” Younha told reporters in an interview held Monday in eastern Seoul ahead of the album’s release on Tuesday.

“The other day, I went to the community center and saw someone who seemed like they had just turned 20 years old. They were getting their first ID and I thought, I should live like that too. Thinking this way was liberating. There were things that I wanted to do when I was 20 but couldn’t, but I could try them again because I’m still young. I tell myself that these days.”

Younha’s “Growth Theory” was released Sunday with 10 tracks all written and composed by Younha as the second in her three-part “Theory” series, which began with her previous full-length album, “End Theory,” in November 2021.

The 2021 album explored people at the end of their relationships, while her most recent work is a story of growth and maturity.

“It all started when I went to Australia to clear my mind,” she said. “I was actually feeling very tense because I had to come up with something for the new album but I had no ideas. The company suggested that I write something about people’s lives and history, but I didn’t want to touch on anything too specific because something too real could easily hurt someone without me intending to do so.”

So, it was in Broome, a city in the northwestern corner of Australia famed for its clear skies that are perfect for stargazing, where the singer found respite from her work last year.

“I was wishing desperately for inspiration when I came across a mangrove forest in Broome,” she said. “Mangroves are very unique types of trees that grow on the borders of the sea and in clear waters. Most trees all absorb clear water, so the mangroves could have been suffocated every day, but they adapted to the environment regardless of their choice. I imagined the trees as real-life people and started imagining their lives.”

The album thus starts with “Mangrove tree,” a song where a 200-year-old mangrove tree is personified as an old woman giving advice to a young girl who is just about to start her adventure into the vast ocean. The story continues with the creatures and objects she meets on her adventure, such as “Antmill,” “Curse for the rocket formula” and “Par of cloud,” leading up to the lead track “Sunfish.”

The ocean sunfish is one of the largest fish species in the world with a unique feature that makes it look like it’s missing the bottom half of its body, when compared to regular fish. It swims from the surface to as low as 800 meters (2,625 feet) underwater, making it versatile — but also unable to stay in one place.

“I saw a bit of myself in the sunfish, which travels from one place to another to find where it belongs,” Younha said. “I tried all kinds of genres during my career, and I wanted to console everyone who suffers from having to care so much about how they’re seen in the society. I feel like that we’re becoming more obsessed with the idea of having a set persona these days, but I want people to know that it’s OK just to wander around here and there.”

In fact, Younha’s very debut started as the story of a “stranger.” Younha traveled alone to Japan at the age of 16 to start her singing career in rock music because Korea, at the time, was even more closed off to the genre than it is now. There, she released her first single “Ubikiri” (2004) and became the talk of the town in Japan with her first album “Go! Younha” (2005) and its lead track “Houki Boshi.”

She made her debut in Korea in 2006 with “Audition (Time2Rock)” and has since filled her discography with some of the biggest hits in the Korean music market, including “Waiting” (2006), “Password 486” (2007), “The Real Reason Why We Broke Up” (2013) and “Event Horizon” (2022), which range from rock and pop to ballad and R&B.

“I feel like it hasn’t been that long since people started opening up to rock music in Korea,” she said. “It was either very ballad or very dance. Rock music was left for the indie singers but now, I’m relieved that it’s become more mainstream. Still, I thought it was crucial that I go my own way regardless of what others think, and that’s why I kept on doing what I did.”

With her latest album, Younha hopes to inspire and encourage listeners to feel motivated enough to start whatever they want.

“There was an online comment that said, ‘I feel like a pirate king after listening to the songs,’ and that was exactly what I wanted to hear,” she said. “I want everyone to feel like they’re the main character of an adventure story and start their journey. I recorded all the songs so that the listeners become overwhelmed with emotion and feel like they can do anything. I’m glad I succeeded on some level.”

The singer said she’s working on the final part of the “Theory” series but didn’t elaborate further. One thing that she is considering, however, is making music for other people.

“Looking into the next 10 years, I can’t help but wonder whether I can keep on singing like I am now,” she said. “I hope I can, and I should as well, but I know that I can’t do as much as I’m doing right now. So I’m thinking about whether I can start something for others, like producing their music, or start something entirely outside of music.”

BY YOON SO-YEON [yoon.soyeon@joongang.co.kr]