On April 1 (KST), the girl group presented a video of the members dancing in white sailor outfits as 'Oh My Boy' with a comeback date of April 5, throwing fans off guard as an April Fool's joke. "Perfect Day" is the 5th track off of their fourth mini-album 'Coloring Book' which will be released on April 3.

Watch the fun video of "Perfect Day" above!

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