Consisting of six tracks heavily featuring pop dance and hip hop, members Momo, Jihyo, Sana, and Chaeyoung participated in the album as songwriters.

The EP also welcomed commercial success, holding the record for having the highest first-week sales for a Korean girl group album until it was surpassed by Twice's succeeding release, Feel Special.

Simultaneously, the group also announced an upcoming world tour on the same day, with concert dates being confirmed for Seoul, Bangkok, Manila, Singapore, Los Angeles, Mexico City, Newark, Chicago, and Kuala Lumpur.

[14] The final teaser for the group's upcoming music video release was uploaded on April 22, revealing the post-hook portion of "Fancy".

The lead single "Fancy" is described as a "bouncing electro-pop track" that retains Twice's retro-inspired sonic base while featuring synth music.

[19] "Hot" is considered to be a pop song featuring distinct guitar riffs, lyrically describing the confidence of a woman who "everyone turns to look at her beauty and is mesmerized by her charisma.

[26] In support of their Fancy You album, the group embarked on their Twicelights World Tour beginning May 2019, visiting Seoul, Bangkok, Singapore, Los Angeles, and Manila, among other cities.

Writer Joshua Calixto described the EP as "a stylistic quantum leap from anything they’d done before, with heavier, darker undercurrents brought by producers like Charli XCX, MNEK, and K-pop superproducer Black Eyed Pilseung."

He further compared the track "Strawberry" to both the attitude emulated by singer Ariana Grande and the simplicity of Selena Gomez's "Bad Liar", while also stating "Girls Like Us" and "Fancy" to be highlights.

"[32] In a more negative review, Cho Ji-hyun of IZM gave a 2 out of 5 rating for Fancy You, noting that the group's attempt to make their music style more mature was unsuccessful with the release of their EP.

While he praised some aspects of song productions, Cho stated that rather than changing music styles completely, the group should have opted for a "skillful digestion" of the members' capabilities.

[34] Fancy You held the record for highest first-week Korean girl group album sales until it was surpassed by Twice's succeeding EP release later in 2019, Feel Special.

[39] In June, the album received a Platinum certification from the Korea Music Content Association for reaching sales of over 250,000 copies.