Dear Raj Shekar,
Firstly:
Even though you are not having any Rental Agreement, you can initiate proceedings against the Tenant for eviction. It is given in the Karnataka Rent Act - 1999, as:
THE KARNATAKA RENT ACT, 1999
Sec. 43. Dispute of relationship of landlord and tenant.-
(1) where in any proceeding before the Court, a contention is raised denying the existence of relationship of landlord and tenant as between the parties it shall be lawful for the Court to accept the document of lease or where there is no document of lease, a receipt of acknowledgement of payment of rent purported to be signed by the landlord as prima-facie evidence of relationship and proceed to hear the case.
(2) Where,-
(a) the lease pleaded is oral and either party denies relationship, and no receipt or acknowledgement of payment of rent as referred to in sub-section (1) above is produced, or
(b) in the opinion of the Court there is reason to suspects the genuine existence of the document of lease or the receipt or acknowledgement of payment of rent.
the Court shall at once stop all further proceedings before it and direct the parties to approach a competent Court of civil jurisdiction for declaration of their rights.
Second:
As you said;
"Till date in last 3 yrs he has not even deposited 3 to 4 months rent in between and not continuously any time. I have come to know of this only recently when i checked my bank statement. "
It is proving his (Tenants) default in payment of Rents, as it is mentioned in the Act under :
Sec. 16. Receipt to be given for rent and other charges paid.-
(1) Every tenant shall pay rent and other charges payable within the time fixed by contract or in the absence of such stipulation, by the fifteenth day of the month next following the month for which it is payable and where any default occurs in the payment of rent or other charges, the tenant shall be liable to pay simple interest at the rate of twelve per cent per annum from the date on which it becomes payable.
OR, as you said:
"I was staying abroad for sometime and i am back now"
YOU CAN
Initiate eviction proceedings against the Tenant under " Bonafied Requirement of the Premises for Self Use " for yourself or your family if any.
Therefore as per me it is your duty to first issue "Demand Legal Notice" to your Tenant for any of the above said Two Ground or for both by contacting a Lawyer there at Banglore and then file Eviction Case against the Tent after notice proceedings. Because Demand Notice is must.