[Nyororin]

LONG nails are one thing - that length in the photo is well within the normal bounds for a guy. At least in my opinion.
My husband bites his nails, and they`re incredibly short... I cannot even begin to express how frustrating it is to watch him have tons of trouble doing the simplest things that would be laughably easy with nails a bit longer. (Picking up flat things off the floor... etc)
I wish he`d grow them out a bit longer, but it seems every time he tries he ends up nibbling on them at work and they disappear again.

As long as they`re not extremely long, are cut cleanly and roundly, and are not painted or anything like that - I wouldn`t think of any guy with long fingernails as feminine. "Well groomed" is more likely the reaction I`d have.