This X post from 

@ujiminphoria
(posted on January 31, 2026) shows a short clip of aespa's Karina and Winter teaming up with Red Velvet's Irene and Seulgi for a special cover of f(x)'s 2009 classic "Chu~♡" during SMTOWN LIVE 2025-26 in Fukuoka, Japan (Day 1).The performance quickly went viral among K-pop fans:
  • It has over 69,000 likes, 18,500 reposts, 3,800+ quotes, and 1.3 million views (as of early February 2026).
  • The clip captures their high-energy stage with synchronized choreography, cute aegyo moments, and strong vocals—perfectly channeling the bubbly, quirky vibe of the original f(x) track.
Fans loved the rare revival of f(x) content (since the group has been inactive since around 2019), and many called it one of the best cross-group collab stages at SMTOWN in recent years. Comments often praised the chemistry between the four idols, their outfits, and how well they nailed the song's playful energy.Full fancams and slightly longer versions quickly appeared on YouTube (search terms like "Irene Seulgi Karina Winter Chu SMTOWN Fukuoka" bring up several uploads with good quality). Some netizens even nicknamed the unit "ASEULKAWIN" or similar playful combos.It's a nostalgic yet fresh moment that highlights SM's legacy acts paying tribute to earlier generations—definitely a highlight of the 2026 SMTOWN tour!