Korean netizens were surprised recently when they recognized a familiar face on season four of 'Single's Inferno.'

One female contestant on 'Single's Inferno 4' captured viewers' attention for her visuals and charm, and was quickly identified as a former trainee who previously appeared on the survival programs 'Produce 48' and 'Idol School.'

One netizen shared a short video of the contestant who introduced herself by saying, "Hello, my name is Lee Si An. I've constantly been in relationships. But right now, I'm single, which is a rare occasion. So I applied because I wanted to experience a fiery, passionate romance."

The netizen questioned, "Is the female contestant on 'Single's Inferno 4' that Lee Si An from 'Produce 48' and 'Idol School'?" Other netizens quickly took notice of the female contestant and recognized who she was. 

They gathered in an online community to comment about Lee Si An and praised that she had gotten more beautiful since her appearance as an idol trainee. They shared:

"I think the last agency where she was a trainee was Stone Music..."

"I figured she must have pivoted to modeling later, but wow, seeing her like this is surprising."

"Wow, she’s amazing. She’s pretty and has so much charm."

"I want to date her."

"Oh, Si An. Si An, I can’t believe I’m seeing you here!"

"I used to vote for Si An during 'Produce 48' and 'Idol School.' I’ve always wondered what she was up to..."

"Wow, she’s so beautiful."

"She fits this so well!"

"She was pretty back then, but she’s even prettier now lol. She’s absolutely stunning."

"She’s gone from having idol-like looks to having actress-like visuals."

"Wow, she’s gotten even more beautiful."

"She was popular back then, too lol."

"I used to vote for her. She’s become even prettier."

"Ah, no wonder her face looked familiar."

"Becoming an idol is really tough... She’s so beautiful."

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