"run fatboy run" ~ Whit
"I can lose weight but you'll always be an asshole" ~ Dennis (exchange between Whit and Dennis during the marathon)
Whit is the main love rival of the romantic comedy "Run Fatboy Run" and is thus the closest thing the movie has to an antagonist - though for much of the movie he is a jerk at worst, however near the end he does arguably cross the line and recieves karmatic retribution as a result.
Whit is introduced as a rich and successful businessman who has began to date Libby, the former fiancee of Dennis Doyle, a roguish anti-hero who left her pregnant on the day of their wedding - yet still has contact with her due to their son (Jake) - who Dennis visits frequently.
Whit and Dennis instantly take a dislike of each other but Whit tries to feign politeness with Dennis at first, though this simply serves to build the resentment between the two and soon Dennis begins to see Whit as a threat, still harboring feelings for Libby despite his past actions.
Thus when Whit decides to run a marathon across London Dennis decides to enter both to prove himself to his doubting friends as well as try and win Libby back - Whit finds his amusing at first but becomes more hostile when it becomes apparent Dennis won't quit.
This climaxes during the marathon itself when Whit tells Dennis to give up and that he had lost, believing Dennis to be a loser Whit informs him he plans on taking Libby and Jake to Chicago and the two start to race faster than anyone else in the marathon while arguing.
Eventually Whit tries to trip Dennis, which results in both men falling and injuring themselves, with Dennis taking the most damage - yet Whit abandons him and tries to finish the race only to quit soon after.
As Whit is taken to hospital he claims Dennis tripped him and that he could sue him but he had little use for "empty pizza boxes" - yet the doctor informs them that Whit is not really hurt and he is allowed to leave, before he leaves the hospital however he loses his temper with Jake (who continually played with his hospital bed) and yelled at him, calling him a "little sh*t" and making Libby uncomfortable.
As a badly injured Dennis continued the marathon despite having a sprained ankle, his actions cause a large crowd to gather and he is soon on national TV - when Whit sees this he is shocked and things soon blow up in his face when the news shows the incident of him deliberately tripping Dennis.
Whit tries to deny that he was responsible and continued to blame Dennis, yet the damage was done and Libby left with Jake - giving him back their engagement ring: in a last ditch effort to get Libby back Whit reminded her Dennis abandoned her on her wedding to which she replied "no one is perfect".
Whit is last seen watching as Dennis finally completes the marathon and becomes angry when he sees Dennis, Libby and Jake together (after Dennis literally falls into their arms) - throwing a temper tantrum before switching off his large TV.