Spongebob Flower

n = 5;
noiseN = 100;
noise = Accumulate@RandomReal[NormalDistribution[0, 1], noiseN + 1];
noiseF = Interpolation[
   Transpose[{Table[t, {t, 0, 2 Pi, 2 Pi/noiseN}], noise}]];
r[t_] := 1 - 0.6 Cos[n t] + 0.02 noiseF[t] Sin[t/2];
\[Theta][t_] := t + 0.15 Sin[2 n t];
ParametricPlot[{r[t] {Cos[\[Theta][t]],
    Sin[\[Theta][t]]}, (0.1 + 0.004 noiseF[t] Sin[t/2]) {Cos[t],
    Sin[t]}}, {t, 0, 2 Pi}, Axes -> None, PlotRange -> All,
 PlotStyle -> Directive[Thick, Purple]]