3 Splash received favourable reviews from music critics who commended the EP's production and commercial appeal.

3 Splash reached number two on the Oricon Singles Chart, and was certified gold by the Recording Industry Association of Japan (RIAJ) for shipments of 100,000 units.

[6] Kumi announced that she would release a new extended play, marketed as a single, entitled 3 Splash, which would consist of three recordings: "Lick Me", "Ecstasy" and "Hashire!"

[8] "Lick Me", the first tracks to include vocals, is an uptempo "cute summer number" with suggestive lyrics.

[8][9] "Ecstasy" is an electronic song with Kumi's "cool husky" vocals being heavily processed with autotune and vocoder effects.

[8][9] According to Adam Greenberg from AllMusic, Ecstasy "share[s] some ideation with Lady Gaga concepts, mixing sultriness with oddity and playing with the instrumentation and voicing along the way.

is a "distorted" midtempo dance song with influences of rock and pop music, and the EP is closed with a final instrumental interlude, "12:00AM".

and the CD+DVD version, which includes a pink-transparent CD holder, features Kher in a 60s-influence dress (which was worn in her "Lick Me" video).

"Ecstasy" was used for Music.Jp, "Lick Me" was used for the televised commercial of her Fever Live in Hall II concert, and "Hashire!"

[12] An alternate version of the music video for "Lick me♥" was later placed on the DVD for her second pachinko game, Fever Live in Hall II.

"[9] Greenberg commended the production of "Ecstasy", and said that "Lick Me" was "slightly off-tempo" that "brings Kumi back to more standard territory.

[8] Hiraga Tetsuo from Hot Express was positive, who commended Kumi's song writing and the "summer" theme throughout the EP.

[25] On the Japanese Oricon Singles Chart, 3 Splash debuted at #2, Kumi's third consecutive EP to have peaked at this position.