No Bite, Just Bark

There are two of them, twin 
mischief; this sizeable house
barely able to contain their antics
their racing rampages up and down
and all around, their challenging
jousts, their breakneck speed
teasing and tousling, two non-stop
motion-madness creatures whose
frenetic energy comes packed in
size small. Do they seek out new
challenges in an excess of hubris
viewing other dogs as unwelcome
contenders to their monopoly on
territory accessible to all? Must
be, as their predictably excited 
greeting leave large dogs puzzled
at the audible and visual racket
that emanates from a duo of
black mobilized fuzzballs, so
brave they flee in terror when
those same large dogs approach
too close for their shrinking comfort
and they hide pitiably behind us.