Judy Sakaki was the Vice Chancellor of Student Affairs from July 2002 until January 2007. This entailed a lot of bureaucratic stuff in Mrak Hall, but she'll still probably payed more attention to you than, say, Stan Nosek, who's in charge of administration. Her office was in 476 Mrak Hall. She's got a little profile c/o some sort of leadership website.
Sakaki indirectly oversaw many aspects of student life, including Campus Unions, Athletics, Advising Services, the UCD Bookstore, Financial Aid, the Registrar, Student Housing, Cowell Student Health Center, and Undergraduate Admissions.
Sakaki was also the administration go-to person on issues of cow tipping.
Judy used to send you a card before your 21st birthday telling you not to die because it makes the University look bad.
She is now the Vice President for Student Affairs at the UC Office of the President.
She didn't send me a card. :( Which is too bad, since that was a point in my life where I really wanted to die. -BrentLaabs