German chap showing excessive love (4)
I believe the answer is:
otto
'german' is the definition.
(common German name)
'excessive love' is the wordplay.
'excessive' becomes 'OTT' (short for 'over the top').
'love' becomes 'o' (love means zero in tennis).
'ott'+'o'='OTTO'
'chap showing' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for otto that I've seen before include "Possibly a German" , "Palindromic fragrance" , "German emperor" , "fragrance comes from?" , "Oil made of rose petals" .)