Get in line, farm hand. Tags of interest include: "pectoral focus", "pectoral grab", "male lactation", "lactation", "male paizuri", "pecjob", "face to pecs", "milking machine". "cow boy" is incidental, comes with the territory. "face to pecs" and "milking machine" are easily the weakest tags, or maybe I don't know how to properly prompt them. Pairing with other tools may give the best results. Pectoral tags and concepts all around should be strongly affected. Hires fix is highly recommended for best results.

If you're interested in sharing your results or getting involved in male-focused Stable Diffusion projects, join us in the #men-only channel on the Unstable Diffusion Discord.