Remove intersect line for one circle using venndiagram2sets

The venndiagram package is very well written and hence easy to customize. I added a style interior B (and also interior A) that can be used as follows:

\fill[white,interior B];

This fills the right circle white. One could add several other similar styles, if needed.

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{backgrounds,positioning}
\usepackage{venndiagram}
\usepackage{float}
\usepackage{showframe}
\makeatletter
\tikzset{interior A/.style={insert path={
 (\@venn@Ax,\@venn@Ay) circle[radius=\@venn@radius-\pgflinewidth/2]}},
 interior B/.style={insert path={
 (\@venn@Bx,\@venn@By) circle[radius=\@venn@radius-\pgflinewidth/2]}}}
\makeatother
\begin{document}

\begin{figure}[H]
    \centering
    \begin{minipage}[t]{0.45\textwidth}
        \begin{venndiagram2sets}[radius=1.3cm,labelA=,labelB=]
            \fillOnlyA
            \setpostvennhook
            {
                \fill[white,interior B];
                \draw (labelA) node[below=6ex] {A\textbackslash B};
                \draw (labelB) node[below=6ex] {B};
            }
        \end{venndiagram2sets}
        \caption{$\mathbf{A}$\textbackslash$\mathbf{B}$}
        \label{fig:venncup}
    \end{minipage}
\end{figure}

\end{document}

A solution with "plain tikz":

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{backgrounds,positioning}
\usepackage{float}
\usepackage{showframe}

\begin{document}

\begin{figure}[H]
    \centering
    \begin{minipage}[t]{0.45\textwidth}
        \begin{tikzpicture}[scale=0.6]
                \draw (-4,-3)rectangle (6,3);
                \fill[gray,draw=black] (0,0)  circle (2cm); 
                \node at (0,0){A\textbackslash B};
                \fill[white,draw=black] (3cm,0) circle  (2cm);
                \node at (3cm,0) {B};
        \end{tikzpicture}
        \caption{$\mathbf{A}$\textbackslash$\mathbf{B}$}
        \label{fig:venncup}
    \end{minipage}
\end{figure}

\end{document}