The correct spelling in the Devanagari script for his name is मनीष (IPA: /mǝniːʂ/
मनीष comes from the Sanskrit word मनीषिन् (IPA: /mǝniːʂin/
My friend's problems arise from him wanting to have a meaningful name and at the same time writing and pronouncing it differently. I haven't mentioned his last name so I think I am safe from the dire consequences promised to me if I ever stooped so low as to reveal this secret of his.
As for me, I will continue to pronounce his name using the voiceless retroflex fricative instead of the voiceless postalveolar fricative.
p.s. 100 extra points for whoever got throught this article without clicking on any of the links.