TvN coming-of-age romance drama “Twenty-Five Twenty-One” came to an end Sunday, landing top ratings for its time slot.

Featuring the strong friendship of teen fencers Na Hee-do (played by Kim Tae-ri) and Ko Yu-rim (Bona) along with high school friends Ji Seung-wan (Lee Ju-myoung) and Moon Ji-woong (Choi Hyun-wook), “Twenty-Five Twenty-One” caught drama fans’ hearts with stories of teenagers pursuing their dreams.

Viewers shared their thoughts about the series in various online communities and platforms, believing that “Twenty-Five Twenty-One” ended by raising many concerns and questions.

Earlier on, the series faced the issue of a potentially controversial student-adult relationship. With Sunday night‘s final episode, many viewers took issue with the presentation of 9/11 terrorist attacks.

Controversy arose concerning scenes where Hee-do laughs watching Yi-jin reporting on 9/11 from New York on TV, happy to see her boyfriend. When Yi-jin makes only a brief appearance, Hee-do expresses disappointment.

Many commenters believed that such a presentation of the tragedy was inappropriate.

“The families and friends of the deceased are still present. And the series is serviced on a global streaming platform, like Netflix. I am disappointed that the drama used the 9/11 terrorist attack like this,” one person commented on a Naver video of the series.

“Think carefully about how you would feel, when an overseas content creator uses Korea’s disaster or catastrophe like this,” another comment read.

The last episode of the series recorded a 12.6 percent viewership rating, down 0.3 percentage point from its highest viewership, according to Nielsen Korea.

The 16-part series ranked fourth place as of Monday on the global Netflix chart, according to US-based streaming analytics firm FlixPatrol.

By Lee Si-jin (sj_lee@heraldcorp.com)