Further detailing of the three categories (not the intimacy level ..... )
Conditions (illness)
Sakuranbo Syndrome - Saliva is required for the cure.
Work (uncommon/cynical profession)
Her Majesty Dog - Kisses as energy source. Uncommon Profession: Ghost Hunter/Detective.
Tokyo Red Hood (closest match I know of - this one is not bad if you keep an open mind ) - Assassination through sexual intercourse. Cynical Profession: Assassins/Syndicate
-I know of other sources relating to this catagory like a movie called Naked Weapon that deals with assassination through heavy physical intimacy and an ova/eroge game titled Bible Black that involves uncommon profession where they collect male sperms for Witchcraft experiments (not a very good example I know...but that's all I can remember ).
Universal Purpose (saving the world/mankind)
Oretama - Foreplay to achieve ejaculation (The Goal).
-Don't mistaken Sundome with this since it's done with personal interests in mind hence a bad example.
Odd request? I know... Just needed something unusual/bizarre to read since I haven't run into much series with these type of similarity, something I found an interest in Need to balance my mind from reading quite a few of these romantic stuff lately, before I turn into a 14 year old school girl...no offense
As usual my lists are at your disposal, much thanks!
Edit: omg ...messed up the title. If a mod would be so kind as to fix it for me, that would be great! Original Intended Title:
Spoiler (highlight to view)
Condition is treated/Work (uncommon/cynical profession) or Universal-Purpose is accomplished through physical intimacy between heterosexual parties.