When it came to the genre of J-R&B, I was more for the soul/funk end of things such as with Masayuki Suzuki（鈴木雅之）and Misia. I wasn't ever a huge fan of hip-hop or rap. But now and then, a few songs from that part of music did reach me, one of them being SOUL'd OUT's "Tongue Te Tongue".
Part of the reason was that Main MC Diggy-MO's vocals struck me as being very interesting to listen to. The other was that catchy refrain including the title that sounds borderline obscene. However, after looking at the lyrics by Diggy-MO and fellow member Bro. Hi, I'm not quite sure what the lyrics are all about. Still, the music by Diggy-MO and other member Shinnosuke is fairly earworm-y.
"Tongue Te Tongue" was SOUL'd OUT's 16th single from October 2007. It peaked at No. 10 and was a track on the group's 4th album "Attitude" from January 2008. It got as high as No. 7 on Oricon. I believe there was a music video with the song but I haven't been able to find it on YouTube.
The group had its run starting from 1999 before disbanding in 2014. They had a total of 20 singles excluding digital downloads and 6 albums.