Compare value against previous value for different column

Question

What is the simplest way to compare one column against the previous value of another column, for each person - ideally without apply/lambda? In this example, "applez" vs "applet"

df     A         B      person
0    fruit    applet     abby
1    applez   cherry     abby
...

df.groupby("person").A.eq(df.groupby("person").B.shift())

Expected Output

0  NaN
1  False