Its probably note bending on a real guitar that was recorded. If you dont have access to a real guitar but only VST, you could try to slide the notes like you would do with 808s in Trap/Drill Beats.theres an effect and instrument that ive been trying to replicate for awhile now.. its like some sort of guitar wah effect...the effect comes out in "Leather so Soft" by "lil wayne" does anyone know how they achieved that sound?