HI Abhishek, 

No it is not necessary to pursue finance-related courses in order to seek admission in a college which offers MBA in Finance. Some of the top colleges offering MBA with specialisation in Finance are-

• IIM Ahmedabad
• IIM Calcutta
• IIM Bangalore
• XLRI, Jamshedpur
• Jamanlal Bajaj Institute of Management Studies, Mumbai
• IIM Indore
• IIM Kozhikode
• IIM Lucknow
• MDI Gurgaon
• S.P. Jain, Mumbai
• IIFT, Delhi
• IIFT, Kolkatta
• FMS, Delhi
• NITIE, Mumbai
• SIBM, Pune
• NMIMS, Mumbai
• IMT Ghaziabad
• IMI New Delhi
• IIT Bombay
• IIM Rohtak
• IIM Ranchi
• IIM Shillong
• SCMHRD Pune
• IIM Raipur
• IIM Udaipur
• IIM Kashipur
• IIM Trichy
• Xavier Institute of Management (XIM), Bhubaneshwar
• IFMR Chennai
• TAPMI, Manipal

To get admission you need to score a very high percentile in CAT examination and also you need to have a strong profile so that you can get a call for second round of WAT & Interview, perform excellently in it and get enrolled in one of the finest management colleges in India.