Uta Kumi 575 (aka Song Builder 575) is part of Sega's Project 575 which utilizes vocaloid voice synthesizers and allows users to control the input of the song lyrics. The story follows two high-school students, Azuki Masaoka and Matcha Kobayashi, who got bored of daily school life and decided to perform songs in haiku-like style and share them across the net. The game consists of story elements which progress through unlockable months that feature anime-style dialogues like a visual novel with full voice-acting where the player can only proceed through the dialogue. That in turn unlocks new songs for the month which can then be played in order to unlock newer and longer songs.
Songs come in three sizes: short, medium and long. Short and medium sizes are unlocked as you play new songs, while long ones need to be bought with the points you gather by performing various songs. The song's size also affects the difficulty level. Unlike a typical vocaloid games such as those from the Hatsune Miku series where you have to press the right button as the notes appear, this game jumbles lyrics making you input the words before they can be sung. Game lyrics are sometimes broken apart so you have to insert them in a correct order to maximize the efficiency of gathering points, but even if you switch the words in an illogical order, they will still be played and you'll be able to get points on properly mashing buttons through those (i.e. words might be entered as "sam-ple" or "ple-sam", with all words in the game being in kana). Sometimes there is only single word selected which requires you to select it quickly before it disappears. Other times, multiple words are offered where only one can be entered, so you decide the lyrics. Often, part of the selectable words are entered (only one kana character) which helps you decide which word to use more quickly. Building lyrics and hitting the right touch screen (front or rear) for the upcoming song notes happens simultaneously.