Subset/Examples/Romeo and Juliet

Example of Subset
Let $B$ denote the set:
 * $B := \set {\textrm {Romeo}, \textrm {Juliet} }$

Let $D$ denote the set:
 * $D := \set {y: \text {$y$ loves Romeo} }$

Then:
 * $B \subseteq D$

presuming, of course, that Romeo actually loves himself, which may be doubted considering he took his own life.