The most common and most likely answer to this crossword clue is the 4 letter word RAKE
I've seen this crossword clue in Financial Times
R
A
K
E
More clues leading to the result RAKE
Buddy explains!

The straight part
We know that "Lothario" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case lothario = rake.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RAKE mean?
RAKE noun- A garden tool with a row of pointed teeth fixed to a long handle, used for collecting debris, grass, etc., for flattening the ground, or for loosening soil; also, a similar wheel-mounted tool drawn by a horse or a tractor.
- (by extension) A similarly shaped tool used for other purposes.
- The act of raking.
- Something that is raked.
- To act upon with a rake, or as if with a rake.
- A walk, or a journey taken (especially on foot); the act of taking a walk or journey.
- The movement of animals while grazing.
- The pastureland over which animals graze; a range, a stray.
- A journey to transport something between two places; a run; also, the quantity of items so transported.
- To walk; to roam, to wander.
- Of animals (especially sheep): to graze.
- To roam or wander through (somewhere).
- A garden tool with a row of pointed teeth fixed to a long handle, used for collecting debris, grass, etc., for flattening the ground, or for loosening soil; also, a similar wheel-mounted tool drawn by a horse or a tractor.
- (by extension) A similarly shaped tool used for other purposes.
- The act of raking.
- Something that is raked.
- A course, a path, especially a narrow and steep path or route up a hillside.
- A fissure or mineral vein of ore traversing the strata vertically, or nearly so.
- (originally Northern England) A series, a succession; specifically a set of coupled rail vehicles, normally coaches or wagons.
- (systems theory) In cellular automata: a puffer that emits a stream of spaceships rather than a trail of debris.
- Rate of progress; pace, speed.
- A divergence from the horizontal or perpendicular; a slant, a slope.
- (specifically) In full, angle of rake or rake angle: the angle between the edge or face of a tool (especially a cutting tool) and a plane (usually one perpendicular to the object that the tool is being applied to).
- The direction of slip during the movement of a fault, measured within the fault plane.
- Senses relating to watercraft.
- (roofing) The sloped edge of a roof at or adjacent to the first or last rafter.
- A person (usually a man) who is stylish but habituated to hedonistic and immoral conduct.
- Rate of progress; pace, speed.
- To move swiftly; to proceed rapidly.
- Of a bird of prey: to fly after a quarry; also, to fly away from the falconer, to go wide of the quarry being pursued.
- A divergence from the horizontal or perpendicular; a slant, a slope.
- (specifically) In full, angle of rake or rake angle: the angle between the edge or face of a tool (especially a cutting tool) and a plane (usually one perpendicular to the object that the tool is being applied to).
- The direction of slip during the movement of a fault, measured within the fault plane.
- Senses relating to watercraft.
- (roofing) The sloped edge of a roof at or adjacent to the first or last rafter.
- To incline (something) from a perpendicular direction.
- Senses relating to watercraft.
- A person (usually a man) who is stylish but habituated to hedonistic and immoral conduct.
- To behave as a rake; to lead a hedonistic and immoral life.