it's an Arabic name, it means war/fight, usually people who hold this name are strong and hot. The spelling originates from Tanzania, it's also spelt "Hareb" in other countries.
Person 1: Hey, my name is Haroub
Person 2: Nice to meet you!
It's a famous phrase, used in the game AQW (Adventure Quest Worlds) as a war-cry of the players.
Player 1: "Battle on!"
Player 2,3,4 & 5: "Battle on!"