What is the drawing on Tomoko's shirt?


In episode 4, Tomoko is using a shirt with a drawing.

[![Mokocchi and her
shirt](https://i.stack.imgur.com/lBwLHm.jpg)](https://i.stack.imgur.com/lBwLH.jpg)

The shirt has a drawing of a face, and すぐる (suguru) written on it.

Since this series makes references to others quite often, I wondered if the
shirt is a reference to something.  
If not, does the shirt have any significance at all?




<http://www.wordsense.eu/Suguru/> seems to define _suguru_ as "male given
name".  
As far as referencing goes, I think it'd be reasonable to say it's just a
picture of a guy's face where an equivalent to "guy" is written underneath.

