Yamagami's first name is so long it is often abbreviated to just "Lucy". Her parents had difficulty choosing a name and listed all the ideas on the registration form. This becomes an ongoing embarrassment for her and she proclaims that she became a civil servant only to exact revenge on the sloppy bureaucrat that approved her name! She becomes angry when people refer to her by first name (or any abbreviation).
Her full first name (or at least as much as she bothered listing) is:
Lucy Kimiko Akie Airi Shiori Rinne Yoshiho Ayano Tomika Chitose Sanae Mikiko Ichika.
However, in the Drama CD Crossover with Working!!, Hiroomi Souma stated her name as:
Yamagami Lucy Kimiko Akie Airi Shiori Rinne Yoshiho Chihoko Ayano Fumika Chitose Sanae Mikiko Ichika Yukino Reina Eri Ai Tamiko Chikage Emilia Julia Shizue Erina Chisa Yumeka Natsuki Ranran Rieko Setsuri Chikako Azumi Marina Hideko Chiaki Misaki Naomi Campbell Miku Yuka Masako Sachiko Nana Mutsumi Haruka Yuna Shimako Yukie Rin Sakura Kanna Wakana Hazuki Honami Ruri Mihane Momoka Himari Nozomi Futaba Mayuyu... (still continues)