The former Ipswich Town boss claims that the Irish players may be surprised by how "placid" his temperament is.
"Hopefully they are in for a pleasant surprise - particularly the lads who haven't worked with me," The Mirror quotes Keane as saying.
"I know people can believe what they hear and read. If they're thinking some monster's going to turn up - and, all of a sudden, I'm quite placid."
Ireland's new head coach Martin O'Neill previously described the duo's partnership as "bad cop and bad, bad cop", but Keane is adamant that he will take on the role of the "good cop".
He added: "I think it's going to be the other way round, I think I am going to have to be the good cop.
"You obviously don't know Martin as well as you think you do. He makes me look like Mother Teresa. It should be interesting."
O'Neill and Keane will take charge of Ireland for the first time this Friday when the national team takes on Latvia.