A deposit bonus is an offer that casino players get once they deposit funds on their player accounts. Casinos use deposit bonuses to attract players to their sites and encourage them to make deposits. The logic behind deposits bonuses is that an extra cash prize will encourage further deposits to the account.
Malaysia is a small South-East Asian country, and a regional economic power horse that attracts new investments to an emerging region. Malaysia is predominantly Muslim country, and all forms of gambling are formally illegal. The ban is loosely enforced. In practice international online and mobile casinos do accept clients from Malaysia.