1 After supporter turns up on foot, kill and go away (4,3)
2 Triglyceride as inert compound (7)
3 Do her nut about strip - it's mad! (5,3,4)
4/21 Supporting Chester on this occasion (3,3,5)
5 Mixed penne with the liquid - you've forgotten what comes after this? (8)
6 Half-arsed practice sessions are damaging arrangements of computers (7)
7 It's simple to return in an environment of vacant detachment, though not normal (7)
12 See 24 Across
16 A bird of passage might fall victim to it (5,3)
17 Moving deviously, partners like a bit of groping (7)
18 Pin shoved up into jacksie - does that ring a bell? (7)
19 Show up as small where sex is involved with expression of laughter (7)
20 'Beheaded fool (beheading difficult in drinking environment) (7)
23 Being an ass for one brief time, right? (6)