Someone who is obsessed with the past can be referred to as a "nostalgist" or "historian" in a general sense. More informally, terms like "nostalgia buff" or "history enthusiast" may also apply. If their obsession is extreme, "anacronist" could be used, though it typically implies a misunderstanding of time periods rather than a mere fascination.
meterologist
meterologist
It could be a chronophile (one who is obsessed about time).
vamp freaks
Lycanmaniac --------------------------------------------------------------------------------------------------------- Lycanophile??
Party pooper?
You !
skull collector
sociopath
Workohalic or social
an astro nut!
Someone who is obsessed with themselves is commonly referred to as narcissistic or self-absorbed.