What do you think about Irene and Seulgi's Red Velvet debut with 'Monster'? - Quora
Red Velvet SeulGi - Kpopmap
Fans Manage To Figure Out The Concept Of Red Velvet's Irene And SeulGi Sub-Unit - Kpopmap
Update: Red Velvet – Irene & Seulgi Reveals Fierce New MV Teaser And Photos For “Monster”
Red Velvet – IRENE & SEULGI - Monster who's who - K-Pop Database /
Seulgi And Irene Open Up About Being Red Velvet's 1st Unit Group, Support From Fellow Members, And More
Red Velvet's Irene And SeulGi Gears Up Sub-Unit Debut With Mirror Selfies - Kpopmap
Fans Furious After Red Velvet – Irene & Seulgi's Subunit Debut Is Delayed… AGAIN - Koreaboo
Viewers startled as Irene's face suddenly changes during the performance of Monster on 'Music Bank