Someone who is obsessed with fighting can be referred to as a "Martial Arts enthusiast" or more colloquially, a "fight junkie." This person often has a deep passion for combat sports, martial arts, or competitive fighting. In some contexts, they may also be described as aggressive or combative, depending on their attitude toward conflict.
meterologist
meterologist
It could be a chronophile (one who is obsessed about time).
an astro nut!
sociopath
skull collector
vamp freaks
Lycanmaniac --------------------------------------------------------------------------------------------------------- Lycanophile??
Party pooper?
You !
Workohalic or social
Someone who is obsessed with themselves is commonly referred to as narcissistic or self-absorbed.