My (short) backstory: Originally, I joined MAL in May 2008, but I completely forgot all the information regarding my original account. I was a member of Anime-planet for a long time, but later I made a full transition to MAL in July 2009 with my current account once I learned you could archive hentai here (dead serious).
I've been a manga mod since September 2011. I originally joined the team to help increase the hentai database. I still do that even now, though these days I spend more time adding non-hentai genre's.
Over my time as a mod, I've added over 7,000+ light novels to the database and that number is steadily rising. That's become my thing around here, or should I say my obsession. If you're interested in what titles I've added to the database, I have everything listed on my "Plan to Read" section. There are a couple not listed there since I'm actively reading some of them.
Back then, there were barely any light novels in the database, so I took it upon myself to become the sole contributor. I didn't start adding light novels until early 2013. These days people submit them regularly so it's a big help (though personally I'd prefer to still do everything myself).