A mortgagee, who holds the mortgaged property also as lessee from the mortgagor, sues the mortgagor to recover Rs 3,000 being the amount of the mortgagee-debt. At the date of the suit the mortgagee owes Rs 4,000 to the mortgagor for rent under the lease, and this sum the mortgagor claims to set-off against the mortgage-debt under an express agreement in that behalf. The agreement is not proved, and a decree is passed against by mortgagee with the leave of the court. The mortgagor then sues the mortgagee to have sale set aside, and for a declaration that the mortgage-debt is extinguished, now claiming that a general account may be taken as between him and the mortgagee, and that in taking such account the rent due to him may be set-off against the mortgage-debt.