Definition
Raasuka is a sub-current of bouyon-muffin developed by Skinny Banton (Shadowflow) from 1995 within the WCK matrix. It belongs to the same time window as bouyon-muffin itself, whose vocal grammar it extends by hardening it.
Sonic character
Where standard bouyon-muffin lays a dancehall ragga toasting on top of the instrumental Bouyon base, raasuka pushes the cursor further: a rougher phrasing, a more rhythmic vocal, less melodic. It is the most radical version of the vocal color Skinny Banton brings to WCK — the one that turns singing into a percussive instrument, not an ornament.
The reference BPM inherits from the bouyon-muffin window (110-135 BPM), held by the TR-505 and the WCK keyboards. It is not a tempo question, it is a vocal-attack question.
Origin
Raasuka is born of the same encounter as bouyon-muffin: Skinny Banton's arrival in WCK in 1995. Skinny does not separate the two lines at the moment of their invention — it is the listening to later tracks and to the pivotal compilation Best of Skinny Banton "Bouyon Muffin" (2010, 22 tracks) that allows, in retrospect, to distinguish the raasuka branch from the standard bouyon-muffin branch. For a fine discographic chronology of each branch, sources are still missing on several points.
Sources: Wikipedia Bouyon music, Spotify Best of Skinny Banton "Bouyon Muffin", Dominica News Online.