what does kisuke mean?

My boyfriend heard this name and really wanted to use it for our son.

It's 喜助 in Kanji?
喜(ki) - joy
助(suke) - help

Kisuke is a very old-fashioned name, not popular today.

I can't recommend Kisuke, because according to the dictionary,
it was used to the name of doing chores at the red light district in the Edo period.

江戸時代、吉原の遊郭で雑用をした若い者の通称
http://dictionary.goo.ne.jp/leaf/jn2/52104/m0u/
江戸の遊里で雑用をする男衆の通称
http://www.weblio.jp/content/%E5%96%9C%E5%8A%A9

I think almost all Japanese don't know that today,
but it's understandable that people in the Edo period was very fond of such word game,
Kisuke for helpers of the red light district.

I agree. Yo native Japanese, Kisuke sounds funny. Not a good name to use in modern days...

OP, are you sure it wasn't Keisuke?