Table with rotated column label

Question

I am trying to make a table where the column label is rotated 90 degrees, I found some code online (see below) and almost got where I wanted. However the lines are not running up completely so column labels are not well separated, also some table "walls" are missing, I would like to fix this issues. Please note there should be a big blank cell (i.e. no walls) in the upper-left side of the table. Any help is very much appreciated.

\documentclass[12pt]{article}
\usepackage{answers}
\usepackage{multicol}
\usepackage{adjustbox}
\usepackage[table,x11names]{xcolor}
\usepackage{float}
\usepackage[utf8]{inputenc}
\usepackage{caption}
\usepackage{array}
\newcolumntype{?}{!{\vrule width 2pt}}
\usepackage[spanish, es-tabla]{babel}
\makeatletter
\renewcommand{\@seccntformat}[1]{}
\makeatother
\setlength\parindent{24pt}

\newcolumntype{R}[2]{%
    >{\adjustbox{angle=#1,lap=\width-(#2)}\bgroup}%
    l%
    <{\egroup}%
}
\newcommand*\rot{\multicolumn{1}{R{90}{1em}}}% no optional argument here, please!
 
\begin{document}
 

\begin{tabular}{r|c|c|c|c|c|}
& \rot{Hello} & 
\rot{Hello} &
\rot{Hello} &
\rot{Hello} &
\rot{Hello} \\
\hline
Hello   & 0 & 0 & 0 & 0 & 0 \\
\hline
Hello   & 0 & 0 & 0 & 0 & 0 \\
\hline
Hello   & 0 & 0 & 0 & 0 & 0 \\ 
\hline
Hello   & 0 & 0 & 0 & 0 & 0 \\
\hline
Hello   & 0 & 0 & 0 & 0 & 0 \\ 
\hline
\end{tabular}


\end{document}

Answer 1

This is a simpler approach (with package rotating).

\documentclass[12pt]{article}

\usepackage{rotating}
\newcommand{\rot}[1]{\begin{turn}{90}#1\enspace\end{turn}}
\newcommand{\mr}[1]{\multicolumn{1}{|c|}{#1}}

\begin{document}    
    
    \begin{tabular}{r|c|c|c|c|c|}
        \cline{2-6}
        & \rot{Hello} & 
        \rot{Hello} &
        \rot{Hello} &
        \rot{Hello} &
        \rot{Hello} \\
        \hline
        \mr{Hello}   & 0 & 0 & 0 & 0 & 0 \\
        \hline
        \mr{Hello}   & 0 & 0 & 0 & 0 & 0 \\
        \hline
        \mr{Hello}   & 0 & 0 & 0 & 0 & 0 \\ 
        \hline
        \mr{Hello}   & 0 & 0 & 0 & 0 & 0 \\
        \hline
        \mr{Hello}   & 0 & 0 & 0 & 0 & 0 \\ 
        \hline
    \end{tabular}   
\end{document}