documentclass{standalone}
usepackage{tikz}

begin{document}
begin{tikzpicture}[scale=1]

tikzstyle{help lines}=[blue!20, very thin];
draw[help lines, step=1mm, very thin] (-10,-10) grid (10,10)
 [help lines, step=1cm, thin] (-10,-10) grid (10,10);


pgfmoveto{pgfpointxy{-1.3}{0}}
pgfpathcurveto{pgfpointxy{-3.3}{-5.3}}{pgfpointxy{-.3}{-5.3}}{pgfpointxy{0}{-5.3}}
pgfpathcurveto{pgfpointxy{.3}{-5.3}}{pgfpointxy{3.3}{-5.3}}{pgfpointxy{1.3}{0}}
pgfpathcurveto{pgfpointxy{3.3}{5.3}}{pgfpointxy{.3}{5.3}}{pgfpointxy{0}{5.3}}
pgfpathcurveto{pgfpointxy{-.3}{5.3}}{pgfpointxy{-3.3}{5.3}}{pgfpointxy{-1.3}{0}}
pgfpathclose
pgfsetstrokeopacity{0.5}
pgfusepath{stroke}

pgfmoveto{pgfpointxy{-1}{0}}
pgfpathcurveto{pgfpointxy{-3}{-5}}{pgfpointxy{-.1}{-5}}{pgfpointxy{0}{-5}}
pgfpathcurveto{pgfpointxy{.1}{-5}}{pgfpointxy{3}{-5}}{pgfpointxy{1}{0}}
pgfpathcurveto{pgfpointxy{3}{5}}{pgfpointxy{.1}{5}}{pgfpointxy{0}{5}}
pgfpathcurveto{pgfpointxy{-.1}{5}}{pgfpointxy{-3}{5}}{pgfpointxy{-1}{0}}
pgfpathclose
pgfsetstrokeopacity{0.5}
pgfusepath{stroke}

foreach y [remember=y as x (initially 0)] in {.1,.2,...,1} {
  pgfpathcurvebetweentime{x}{y}{pgfpointxy{-1.3}{0}}{pgfpointxy{-3.3}{-5.3}}{pgfpointxy{-.3}{-5.3}}{pgfpointxy{0}{-5.3}}
 pgfpathlineto{pgfpointcurveattime{y}{pgfpointxy{-1}{0}}{pgfpointxy{-3}{-5}}{pgfpointxy{-.1}{-5}}{pgfpointxy{0}{-5}}}
 pgfpathcurvebetweentimecontinue{y}{x}{pgfpointxy{-1}{0}}{pgfpointxy{-3}{-5}}{pgfpointxy{-.1}{-5}}{pgfpointxy{0}{-5}}
 pgfpathclose
 pgfsetstrokeopacity{1}
 pgfusepath{stroke}
};

end{tikzpicture}
end{document}