Zombie-mode or not?

I've been lying on my bed and thinking if I should really start to get serious on this game. I mean, I'm a casual player. I feel like getting Juno but I need to rank at top 500 to get at least 1 or her. I checked my items but only 1 Light Sword resting there miserably. I want to get Juno... She's cute... Then I remembered the VC news about a boy's death because he did not sleep, just focusing on getting Netherworld Princess. I don't want to end up like him either... But I've got studies and I can't purchase all those swords with my Jewel amount. I've been trying to be thrifty. You will surely bet I'm thinking if I should tell my parents that after I graduate, should I start spending some bucks here and there. To prove I like this game to my parents, that is an easy task but how much should I spend? I will have limited amounts of money to spend for sure, so I'm not sure how much is enough for me to at least reach top 500 in an event with at least 15 BP as my max. And roughly how much time should I spend on playing VC to get that rank? I don't want to spend all my precious time on VCing and enter Zombie-mode. Could some people give me advice? Thanks. And add me if you want. 4hfd5.