- Rakuyou (落陽; Setting Sun)
- Party Night (パーリィナイッ)
- Rakuyou ~ryukyu acoustic mix~ (落陽; Setting Sun)
- The single Rakuyou was actually released two weeks after the song appeared in 1st Contact.
- This single is the first to feature a regular and limited edition; the limited edition includes a DVD with the music video to "Rakuyou".
- "Rakuyou" has a short version and a long version, the latter of which was recorded for the album.
- "Rakuyou" is a semi-ballad; the PV features Yamato playing the Sanshin, but Naoto plays it on the CD. Ryo's rap at the end of the song was re-recorded multiple times.
- For the song-by-request, fan club exclusive tour "AID JAM 007", "Rakuyou" was the number one most requested song.
- "Rakuyou ~ryukyu acoustic mix~" reflected the band's Ryukyu image (Ryukyu being Okinawa).