I'm so happy my brothers are normal! As for dealing with your eccentric bro, let's fix the problems in order.
1. the leak: store the bottle in a ziploc bag and get a new empty bottle to decant the contents.
2. the excessive spraying: after he lost his sense of taste, he learned his lesson. Teach him maximum number of sprays for each scent, and emphasize the concept of "cologne guy".
3. the brother: the world would be boring if it weren't for eccentric people. I'm sure he has redeeming qualities!