Abstract: Successful fusion pilot plant (FPP) design hinges upon the ability to predict and control exhaust conditions, to maximize the lifetime of plasma-facing components. This work describes a pathway toward high-fidelity, first-principles simulations with predictive capabilities for plasma particle fueling and detachment. It presents the coupling of a continuum full-f gyrokinetic turbulence model with a 6D continuum model for kinetic neutrals, carried out using the Gkeyll code, which has been extended to include general geometry capabilities using a canonical Poisson Bracket formalism. A successful exhaust design will rely on both neutral interactions and plasma shaping in order to reduce the flux of heat and particles to the divertor without degrading core plasma conditions. We explore these effects through simulations of DIII-D inner-wall-limited (IWL) plasmas. For example, negative triangularity plasmas exhibit good confinement properties without the presence of disruptive edge localized modes (ELMs). We present the differences in profiles and turbulence dynamics in negative and positive triangularity geometries. Results demonstrate good agreement with experimental data.