To Obtain this you must complete Phyllis' Romance Mission "Phyllis's Dream".
In order for this to show up you must:
A- Complete South Block
B- Be Lovers with Phyllis
C- Complete the previous Romance Mission "Time to Get Serious". Note that you must Propose to Phyllis [She will Decline] before this Mission will Flag to start, and at least One Day must Pass after its Completion for Phyllis' Dream to become Available.