Please be warned that some of this information can be considered spoilers, so read at your own risk.
Harem Members (So Far): Rowena Ravenclaw, Hermione Granger, Luna Lovegood, Bellatrix Lestrange, Fleur Delacour, Olivier Armstrong, and Wiz from Konosuba.
Magical Rank:
Tier 0: Apprentice.
Tier 1-Tier 3: Breaking the Limiters.
Tier 4 Country Level.
Tier 5 Continental Level.
Tier 6 Planetary Level.
Tier 7 Star Level.
Tier 8 Solar System level.
Tier 9 Galaxy Level.
Tier 10 Universe Level.
Tier 11 Multiverse Level.
The higher tiers have been introduced but not formally. (If you know what chapter I'm talking about, good for you for paying attention.)
World Traveled To:
1. Harry Potter (Home universe where everything begins and where the main story takes place.)
2. Full Metal Alchemist Brotherhood.
3. A combination of many movies, including The Jungle Movie, All four Mummy movies (Including the Reboot, The Library (Only the movies, not the TV Show), The Last Witch Hunter, and Indiana Jones.
4. Black Clover and Konosuba.
5. Naruto.