*Gag series, slapstick, parodies, macabre humor, toilet humor.
*Long serious fight scenes, preferably with lots of blood.
*Lots of character development & background stories.
*Subplot where dude wants to get out of the Friendzone with token chick character.
*Subplot where girl hopes senpai will notice her.
*Harem of super girly girls in fanservicey clothing, especially if they're fawning over the same guy.
*Unrequited love injecting tons of drama & angst so a series that should only have humor & fighting.
Exceptions where it's okay:
*Unrequited love played as a running gag between a comedic stalker & an thoroughly uninterested hero who uses said stalker as a punching bag. (Think of Kondou or Sarutobi from Gintama or the sisters from Sorcerer Hunters).
*The harem of fanservice girls is okay if it's 1)only expendable background characters, or 2)if it's just for looks & the women are serious & too focused on their mission & team to care about petty romance, or 3)if the object of their affection is pure & oblivious to love. (Like Photon).
*Starts off with potential romance, then latter sinks all the ships (like maybe the love interest turns out to be a long-lost sibling or an undercover enemy with a grudge).
*The characters are already married or dating from the start.
*The person is love is the series buttmonkey/chew toy, who pines after a reprehensible sadist.. (Sarutobi, Kondou, Mosquiton, Grell, Excel).
*Kill la Kill.
*Hunter x Hunter.
*Slayers Next/Try/Revolution/Evolution R.
*Sorcerous Stabber Orphan 2: Revenge.
*Gokudo-Kun Manyuuki. (Gokudo: Swordsman Extraordinaire).
*Bakuretsu Hunter. (Sorcerer Hunters).
*Photon: The Idiot Adventures.
*Master of Mosquiton 99.
*The 2ed half of Majin Tantei Nougami Neuro, which was sadly never animated.
Still waiting for the next chapter of Hunter x Hunter.
Ben-To (lead is oblivious to growing harem around him, and mostly just focused on getting cheap dinner)